PROASSURANCE CORP (PRA) FY 2023 MD&A

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion generally focuses on the change in financial condition, results of operations and cash flows for the year ended December 31, 2023 as compared to the year ended December 31, 2022 and should be read in conjunction with the Consolidated Financial Statements and Notes to those statements which accompany this report. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2022 report on Form 10-K. Any significant retrospective revisions in the presentation of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021 as reported in ProAssurance's December 31, 2022 report on Form 10-K are located in this report under the section that follows titled "Results of Operations - Year Ended December 31, 2022 Compared to Year Ended December 31, 2021."

Throughout the discussion we use certain terms and abbreviations, which can be found in the Glossary of Terms and Acronyms at the beginning of this report. In addition, a glossary of insurance terms and phrases is available on the investor section of our website. Throughout the discussion, references to "ProAssurance," "PRA," "Company," "organization," "we," "us" and "our" refer to ProAssurance Corporation and its consolidated subsidiaries. The discussion contains certain forward-looking information that involves significant risks, assumptions and uncertainties. As discussed under the heading "Caution Regarding Forward-Looking Statements," our actual financial condition and results of operations could differ significantly from these forward-looking statements.

ProAssurance Overview

ProAssurance Corporation is a holding company for property and casualty insurance companies. Our insurance subsidiaries provide professional liability insurance, liability insurance for medical technology and life sciences risks and workers' compensation insurance.

We have also provided capital to Syndicate 1729 at Lloyd's of London to support our previous participation in underwriting years that remain open. Effective September 2023, we elected to discontinue our participation in the results of Syndicate 1729 beginning with the 2024 underwriting year. The results from our participation in Syndicate 1729 from open underwriting years prior to 2024 will continue to earn out pro rata over the entire policy period of the underlying business. Due to the quarter lag, our ceased participation in Syndicate 1729 will begin to be reflected in our results in the second quarter of 2024. Furthermore, we received proceeds of $6.8 million during 2023 associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties.

Our operating segments are based on our internal management reporting structure for which financial results are regularly evaluated by our CODM to determine resource allocation and assess operating performance. As a result of our decision to no longer participate in the results of Syndicate 1729 beginning with the 2024 underwriting year, we reorganized our segment reporting during the third quarter of 2023 to align with how our CODM currently oversees the business, allocates resources and evaluates operating performance and, as a result, the number of our operating and reportable segments decreased from five to four: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance and Corporate. As a result of the segment reorganization, we now report the underwriting results from our participation in Lloyd’s Syndicates in the Specialty P&C segment and the investment results of assets solely allocated to our Lloyd's Syndicate operations and U.K. income taxes in our Corporate segment. All prior period segment information has been recast to conform to the current period presentation and the segment reorganization had no impact on previously reported consolidated financial results.

Additional information on ProAssurance's four operating and reportable segments is included in Note 16 of the Notes to Consolidated Financial Statements, Part I and in the Segment Results sections herein that follow.

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Growth Opportunities and Outlook

Over the long-term we expect our growth to come primarily through controlled expansion of our existing operations. In addition, we may identify opportunities for growth through the acquisition of other insurers, service providers or books of business.

We operate in very competitive markets and face strong competition from other insurance companies for all of our insurance products. Our Specialty P&C segment includes our HCPL insurance which represents the largest product line in our consolidated gross premiums written (59% in 2023). The Specialty P&C segment also includes our Small Business Unit (9% in 2023), Medical Technology Liability (4% in 2023) and Lloyd's Syndicates (2% in 2023) lines of business. The healthcare market in the U.S. is continuing to consolidate, which brings competitive challenges and opportunities. This consolidation initially took the form of hospitals acquiring physician practices and later the growth of physician groups owned by outside investors. As these trends continue, most physicians no longer practice medicine as owners of an independent practice. Large single and multi-specialty practices often operate in many states. Healthcare delivery settings are changing with the growth of retail delivery by allied healthcare professionals as well as physicians practicing in distributed clinics, pharmacies, large consumer stores and online. These larger commercial enterprises have differing risk management needs from those in the traditional small physician practices. As such, we have enhanced our coverage offerings to fit the needs of combined hospital/physician entities, multi-state medical groups, telemedicine companies, miscellaneous facilities, allied healthcare professionals and self-insured entities even as we continue to service that portion of the market maintaining more traditional practice structures. Our Medical Technology Liability and Small Business Unit lines of business are less affected by these consolidation trends.

In 2024, we plan to restructure the Small Business Unit line of business within our Specialty P&C segment and focus on the automation of specific products. Our goal in 2024 is to develop a fully automated platform initially focused on allied healthcare, advanced practice clinicians and dental professional liability coverages. To achieve this goal, we plan to move the podiatric, chiropractic, and dental coverages from the Small Business Unit into HCPL, forming a new unit called Medical Professional Liability. By combining these resources, ProAssurance will have a single unit dedicated to all of its healthcare insurance specialty areas and be able to meet customer needs more efficiently and effectively in order to better serve this market.

Our operations at Eastern, a provider of workers' compensation insurance, represents the second largest product line in our consolidated gross premiums written (23% in 2023, including alternative market premiums). The workers’ compensation market is highly competitive in our operating territories and multi-line insurers continue to leverage workers’ compensation in their product offerings. Additionally, the rates we charge our policyholders remain pressured by the continuation of loss cost decreases in the states within our operating territories, and most states in which we operate have approved additional loss cost decreases for 2024. Despite the competitive workers' compensation market conditions new business writings increased, while renewal retention remained strong. We believe our workers' compensation product offerings allow us to provide flexibility in offering solutions to our customers at a competitive price.

We believe our emphasis on the fair treatment of our insureds and other important stakeholders through our commitment to “Treated Fairly” has enhanced our market position and differentiated us from other insurers. We will continue to uphold our values of integrity, leadership, relationships and enthusiasm in all of our activities. We will honor these values in the execution of “Treated Fairly” to perform our Mission and realize our Vision. We believe that as we reach more customers with this message we will continue to improve retention and add new insureds.

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Key Performance Measures

We are committed to disciplined underwriting, pricing and loss reserving practices as well as an effective investment strategy, even during difficult market conditions. We are also committed to maintaining prudent operating and financial leverage. We recognize the importance that our customers and producers place on the financial strength of our insurance subsidiaries, and we manage our business to protect our financial security.

In evaluating our performance, we consider a number of performance measures, including the following:

•The net loss ratio which is calculated as net losses and loss adjustment expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The underwriting expense ratio which is calculated as underwriting, policy acquisition and operating expenses incurred divided by net premiums earned and is a component of underwriting profitability.

•The combined ratio which is the sum of the net loss ratio and the underwriting expense ratio and measures underwriting profitability.

•The investment income ratio which is calculated as net investment income divided by net premiums earned and measures the contribution investment earnings provide to our overall profitability.

•The operating ratio which is the combined ratio, less the investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income.

•The effective tax rate which is calculated as total income tax expense (benefit) divided by income (loss) before income taxes.

•Non-GAAP operating income (loss) which is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we exclude the effects of items that do not reflect normal operating results. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our insurance operations; however, it should be considered in conjunction with net income (loss) computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•ROE which is calculated as net income (loss) divided by the average of beginning and ending shareholders’ equity. This ratio measures our overall after-tax profitability and shows how efficiently capital is being used.

•Non-GAAP operating ROE which is calculated as Non-GAAP operating income (loss) for the period divided by the average of beginning and ending total GAAP shareholders’ equity. Non-GAAP operating ROE measures the overall after-tax profitability of our insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

•Book value per share which is calculated as total shareholders’ equity divided by the total number of common shares outstanding at the balance sheet date. This ratio measures the net worth of the Company to shareholders on a per-share basis. The declaration of dividends decreases book value per share. Growth in book value per share, adjusted for dividends declared, is an indicator of overall profitability.

•Non-GAAP adjusted book value per share which is a Non-GAAP measure widely used within the insurance sector and is calculated as shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. See a reconciliation to its GAAP counterpart in the Executive Summary of Operations section under the heading “Non-GAAP Financial Measures” that follows.

In particular, we focus on our combined ratio and investment returns, both of which directly affect our ROE and growth in our book value per share. Currently, we target a dynamic long-term ROE of 700 basis points above the 10-year U.S. Treasury rate, which at December 31, 2023 was approximately 10.9%.

To achieve our long-term ROE target, we emphasize rate adequacy, selective underwriting, effective claims management, operational efficiency gained by leveraging our enhanced scope and scale and prudent investment management. We closely monitor premium revenues, losses and loss adjustment expenses, and underwriting and policy acquisition expenses. Our overall investment strategy is to focus on maximizing current income from our investment portfolio while maintaining appropriate credit risk, liquidity, duration, portfolio diversification and capital efficiency. While we engage in activities that generate other income, these activities, such as insurance agency services, do not constitute a significant use of our resources or a significant source of revenues or profits.

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Critical Accounting Estimates

Our Consolidated Financial Statements are prepared in conformity with GAAP. Preparation of these financial statements requires us to make estimates and assumptions that affect the amounts we report on those statements. We evaluate these estimates and assumptions on an ongoing basis based on current and historical developments, market conditions, industry trends and other information that we believe to be reasonable under the circumstances. We can make no assurance that actual results will conform to our estimates and assumptions; reported results of operations may be materially affected by changes in these estimates and assumptions.

Management considers the following accounting estimates to be critical because they involve significant judgment by management and those judgments could result in a material effect on our financial statements.

Reserve for Losses and Loss Adjustment Expenses

The largest component of our liabilities is our reserve for losses and loss adjustment expenses ("reserve for losses" or "reserve"), and the largest component of expense for our operations is incurred losses and loss adjustment expenses (also referred to as “losses and loss adjustment expenses,” “incurred losses,” “losses incurred” and “losses”). Incurred losses reported in any period reflect our estimate of losses incurred related to the premiums earned in that period as well as any changes to our previous estimate of the reserve required for prior periods.

As of December 31, 2023, our reserve is comprised almost entirely of long-tail exposures. The estimation of long-tailed losses is inherently complex and is subject to significant judgment on the part of management. Due to the nature of our claims, our loss costs, even for claims with similar characteristics, can vary significantly depending upon many factors, including but not limited to the specific characteristics of the claim and the manner or jurisdiction in which the claim is resolved. Long-tailed insurance is characterized by the extended period of time typically required both to assess the viability of a claim and potential damages, if any, and to reach a resolution of the claim. The claims resolution process may extend to more than five years. Further, the industry has experienced new conditions, including changes in settlement trends as a result of COVID-19 due to the effect of the postponement of court cases during the pandemic. The combination of continually changing conditions and the extended time required for claim resolution results in a loss cost estimation process that requires actuarial skill and the application of significant judgment, and such estimates require periodic modification.

Our reserve is established by management after taking into consideration a variety of factors including premium rates, historical paid and incurred loss development trends and our evaluation of the current loss environment including frequency, severity, expected effects of inflation (monetary, social and medical), general economic and social trends, and the legal and political environment. The effect of COVID-19 on recent historical trends regarding timing and severity of claims may also impact certain of these factors and our ultimate estimation of losses. We also take into consideration the conclusions reached by our internal and consulting actuaries. We update and review the data underlying the estimation of our reserve for losses each reporting period and make adjustments to loss estimation assumptions that we believe best reflect emerging data. Both our internal and consulting actuaries perform an in-depth review of our reserve for losses on at least a semi-annual basis using the loss and exposure data of our insurance subsidiaries.

We partition our reserves by accident year, which is the year in which the claim becomes our liability. For claims-made policies, the insured event generally becomes a liability when the event is first reported to us. For occurrence policies, the insured event becomes a liability when the event takes place. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. As claims are incurred (reported) and claim payments are made, they are aggregated by accident year for analysis purposes. We also partition our reserves by reserve type: case reserves and IBNR reserves. Case reserves are established by our claims departments based upon the particular circumstances of each reported claim and represent our estimate of the future loss costs (often referred to as expected losses) that will be paid on reported claims. Case reserves are decremented as claim payments are made and are periodically adjusted upward or downward as estimates regarding the amount of future losses are revised; reported loss for an individual claim is the case reserve at any point in time plus the claim payments that have been made to date. IBNR reserves are estimated by accident year by our actuarial department and represent our estimate in the aggregate of future development on losses that have been reported to us and our estimate of losses that have been incurred but not reported to us.

Our reserving process can be broadly grouped into three areas: the establishment of the reserve for the current accident year (the initial reserve), the re-estimation of the reserve for prior accident years (development of prior accident years) and the establishment of the initial reserve for risks assumed in business combinations, applicable only in periods in which acquisitions occur (the acquired reserve). A summary of the activity in our net reserve for losses during 2023 and 2022 is provided under the heading "Losses" in the Liquidity and Capital Resources and Financial Condition section that follows.

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Current Accident Year - Initial Reserve

Considerable judgment is required in establishing our initial reserve for any current accident year period, as there is limited data available upon which to base our estimate (see further discussion that follows under the heading "Use of Judgment"). Our process for setting an initial reserve considers the unique characteristics of each product, but in general we rely heavily on the loss assumptions that were used to price business, as our pricing reflects our analysis of loss costs that we expect to incur relative to the insurance product being priced.

Specialty P&C Segment. Loss costs within this segment are impacted by many factors including but not limited to the nature of the claim, including whether or not the claim is an individual or a mass tort claim, the personal situation of the claimant or the claimant's family, the outcome of jury trials, the legislative and judicial climate where any potential litigation may occur, general economic and social trends and the trend of healthcare costs. Within our Specialty P&C segment, for our professional liability business (87% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2023; predominately comprised of our HCPL products), we set an initial reserve using a loss ratio approach based upon our evaluation of the current loss environment including frequency, severity, monetary inflation, social inflation and legal trends. See further discussion in our Segment Results - Specialty Property & Casualty section that follows under the heading "Losses and Loss Adjustment Expenses."

The risks insured in our Medical Technology Liability business (3% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2023) are more varied, and policies are individually priced based on the risk characteristics of the policy and the account. The insured risks range from startup operations to large multinational entities, and the larger entities often have significant deductibles or self-insured retentions. Reserves are established using our most recently developed actuarial estimates of losses expected to be incurred based on factors which include results from prior analysis of similar business, industry indications, observed trends and judgment. Claims in this line of business primarily involve bodily injury to individuals and are affected by factors similar to those of our HCPL line of business. For the Medical Technology Liability business, we also establish an initial reserve using a loss ratio approach, including a provision in consideration of historical loss volatility that this line of business has exhibited.

Workers' Compensation Insurance Segment. Many factors affect the ultimate losses incurred for our workers' compensation coverages (6% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2023) including but not limited to the type and severity of the injury, the age, health and occupation of the injured worker, the estimated length of disability, medical treatment and related costs, and the jurisdiction and workers' compensation laws of the state of the injury occurrence.

We use various actuarial methodologies in developing our workers’ compensation reserve, combined with a review of the payroll exposure base. For the current accident year, given the lack of seasoned information, the different actuarial methodologies produce results with significant variability; therefore, more emphasis is placed on supplementing results from the actuarial methodologies with trends in exposure base, medical expense inflation, general inflation, severity, and claim counts, among other things, to select an ultimate loss indication.

Segregated Portfolio Cell Reinsurance Segment. The factors that affect the ultimate losses incurred for the workers' compensation and HCPL coverages assumed by the SPCs at Inova Re and Eastern Re (2% of our consolidated gross reserve for losses and loss adjustment expenses as of December 31, 2023) are consistent with that of our Workers’ Compensation Insurance and Specialty P&C segments, respectively.

Development of Prior Accident Years

In addition to setting the initial reserve for the current accident year, we reassess the amount of reserve required for prior accident years each period.

The foundation of our reserve re-estimation process is an actuarial analysis that is performed by both our internal and consulting actuaries. This detailed analysis projects ultimate losses based on partitions which include line of business, geography, coverage layer and accident year. The procedure uses the most representative data for each partition, capturing its unique patterns of development and trends. We believe that the use of consulting actuaries provides an independent view of our loss data as well as a broader perspective on industry loss trends.

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The analyses performed by the consulting actuaries analyzes each partition of our business in a variety of ways and uses multiple actuarial methodologies in performing these analyses, including:

•Bornhuetter-Ferguson (Paid and Reported) Method

•Paid Development Method

•Reported (Incurred) Development Method

•Average Paid Value Method

•Average Reported Value Method

A brief description of each method follows.

Bornhuetter-Ferguson Method. We use both the Paid and the Reported Bornhuetter-Ferguson Methods. The Paid Method assigns partial weight to initial expected losses for each accident year (initial expected losses being the first established case and IBNR reserves for a specific accident year) and partial weight to paid to date losses. The Reported Method assigns partial weight to the initial expected losses and partial weight to current reported losses. The weights assigned to the initial expected losses decrease as the accident year matures.

Paid Development and Reported (Incurred) Development Methods. These methods use historical, cumulative losses (paid losses for the Paid Development Method, reported losses for the Reported (Incurred) Development Method) by accident year and develop those actual losses to estimated ultimate losses based upon the assumption that each accident year will develop to estimated ultimate cost in a manner that is analogous to prior years, adjusted as deemed appropriate for the expected effects of known changes in the claim payment environment (and case reserving environment for the Reported (Incurred) Development Method); and to the extent necessary, supplemented by analyses of the development of broader industry data.

Average Paid Value and Average Reported Value Methods. In these methods, average claim cost data (paid claim cost for the Average Paid Value Method and reported claim cost for the Reported Value Method) is developed to an ultimate average cost level by report year based on historical data. Claim counts are similarly developed to an ultimate count level. The average claim cost (after rounding and adjustment, if necessary, to accommodate report year data that is not considered to be predictive) is then multiplied by the ultimate claim counts by report year to derive ultimate loss and ALAE.

We use various actuarial methods in the process of setting reserves. Each actuarial method generally returns a different value, and for the more recent accident years the variations among the different methodologies can be significant. Generally, methods such as the Bornhuetter-Ferguson Method are used on more recent accident years where we have less data on which to base our analysis. As time progresses and we have an increased amount of data for a given accident year, we begin to give more confidence to the development and average methods, as these methods typically rely more heavily on our own historical data. These methods emphasize different aspects of loss reserve estimation and provide a variety of perspectives for our decisions.

Certain of the methodologies utilized to estimate the ultimate losses for each partition of our reserves consider the actual amounts paid. Paid data is particularly influential when a large portion of known claims have been closed, as is the case for older accident years. In selecting a point estimate for each partition, management considers the extent to which trends are emerging consistently for all partitions and known industry trends. Thus, actual, rather than estimated severity trends are given more consideration. If actual severity trends are lower than those estimated at the time that reserves were previously established, the recognition of favorable development is indicated. This is particularly true for older accident years where our actuarial methodologies give more weight to actual loss costs (severity).

The various actuarial methods discussed above are applied in a consistent manner from period to period. For each partition of our reserves, we evaluate the results of the various methods, along with the supplementary statistical data regarding such factors as closed with and without indemnity ratios, claim severity trends, the expected duration of such trends, changes in the legal and legislative environment and the current economic environment to develop a point estimate based upon management's judgment and past experience. The series of selected point estimates is then combined to produce an overall point estimate for ultimate losses.

We utilize the selected point estimates of ultimate losses to develop estimates of ultimate losses recoverable from reinsurers, based on the terms and conditions of our reinsurance agreements. An overall estimate of the amount receivable from reinsurers is determined by combining the individual estimates. Our net reserve estimate is the gross reserve point estimate less the estimated reinsurance recovery.

For our Workers’ Compensation Insurance segment and for the workers' compensation exposures in our Segregated Portfolio Cell Reinsurance segment, we utilize the Reported (Incurred) Development Method, Paid Development Method and Bornhuetter-Ferguson Method, to develop our reserve for each accident year. The actuarial review includes the stratification of claims data (lost time claims, medical only claims) using different variations that allow us to identify trends that may not be readily identifiable if the data was evaluated only in the aggregate. Reported and paid loss development factors are key assumptions in the reserve estimation process and are based on our historical reported and paid loss development patterns. As accident years mature, the various actuarial methodologies produce more consistent loss estimates.

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Acquired Reserve

The acquisition of NORCAL on May 5, 2021 increased our gross reserves by $1.2 billion which was the fair value of NORCAL's gross loss reserve at the time of acquisition. The fair value estimate of NORCAL's gross reserve for losses and loss adjustment expenses was based on three components: an actuarial estimate of the expected future net cash flows, a reduction to those cash flows for the time value of money determined utilizing the U.S. Treasury Yield Curve and a risk margin adjustment to reflect the net present value of profit that an investor would demand in return for the assumption of the development risk associated with the reserve. The fair value of NORCAL's gross reserve, including the risk margin adjustment, exceeded the actuarial estimate of NORCAL’s undiscounted gross loss reserve by approximately $42.2 million as of May 5, 2021. This fair value adjustment was recorded to the reserve for losses and loss adjustment expenses and will be amortized over a period utilizing loss payment patterns as a reduction to prior accident year net losses and loss adjustment expenses. We also recorded other adjustments to NORCAL’s reserve as a result of purchase accounting including negative VOBA on NORCAL’s assumed unearned premium and assumed DDR reserve.

Use of Judgment/Variability of Loss Reserves

The process of estimating reserves involves a high degree of judgment and is subject to a number of variables. These variables can be affected by both views of internal and external events, such as changes in views of monetary and social inflation, legal trends and legislative changes, as well as differentiating views of individuals involved in the reserve estimation process, among others. We continually refine our estimates in a regular, ongoing process as historical loss experience develops and additional claims are reported and settled. Our objective is to consider all significant facts and circumstances known at the time.

Our loss reserves may be impacted by social inflation, which is generally described as the rising costs of insurance claims resulting from factors including, but not limited to, increasing litigation, broader definitions of liability, more plaintiff-friendly legal decisions, jury behavior, and larger compensatory jury awards and non-economic damages. These factors could lead to greater than anticipated claims and claim handling expenses which could exceed our established reserves causing us to increase our loss reserves.

The effects of monetary and medical inflation could cause the cost of claims to rise in the future. Our loss reserves include assumptions about future payments for settlement of claims and claims handling expenses, such as medical treatments and litigation costs. For our workers' compensation reserves, healthcare wage inflation and medical advancements may also increase the cost of claims. To the extent inflation causes these costs to increase above reserves established for these claims, we will be required to increase our loss reserves with a corresponding reduction in our financial results in the period in which the need for additional reserves is identified.

HCPL. Over the past several years the most influential factor affecting the analysis of our HCPL reserves and the related development recognized has been an observed increase in claim severity for the broader medical professional liability industry as well as higher initial loss expectations on incurred claims. The severity trend is an explicit component of our pricing models and directly impacts the reserving process. Our estimate of this trend and our expectations about changes in this trend impact a variety of factors, from the selection of expected loss ratios to the ultimate point estimates established by management.

Because of the implicit and wide-ranging nature of severity trend assumptions on the loss reserving process, it is not practical to specifically isolate the impact of changing severity trends. However, because severity is an explicit component of our HCPL pricing process we can better isolate the impact that changing severity can have on our loss costs and loss ratios in regards to our pricing models for this business component. Our current HCPL pricing models assume severity trends in the range of 2% to 6% depending on state, territory and specialty. In some portions of our HCPL business we have observed and reflected higher severity trends in our estimates of losses and loss adjustment expenses.

Due to the long-tailed nature of our claims and the previously discussed historical volatility of loss costs, selection of a severity trend assumption is a subjective process that is inherently likely to prove inaccurate over time. Given the long tail and volatility, we are generally cautious in making changes to the severity assumptions within our pricing models. All open claims and accident years are generally impacted by a change in the severity trend, which compounds the effect of such a change.

Although the future degree and impact of the ultimate severity trend remains uncertain due to the long-tailed nature of our business, we have given consideration to observed loss costs in setting our rates. For our HCPL business, this practice has recently resulted in rate increases reflecting the rising loss cost environment, and we anticipate further renewal pricing increases due to increasing loss severity.

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Workers' Compensation. In our workers’ compensation business, severity is not an explicit component of our pricing process, as loss costs are established by the states in which we operate. We do, however, have the ability in certain states to apply for increases in our loss cost multipliers to adjust for company specific loss experience that is higher than state loss cost changes. In our reserving process, we consider the loss severity trends in evaluating both our current and expected loss development. Historically, we have been able to minimize the impact of higher severity trends as a result of our early intervention and case management strategies in our claims process, which results in claims being resolved more quickly than the industry norm. However, in the second half of 2023, we observed higher than expected loss trends in our average cost per claim which we primarily attribute to increased medical costs driven by wage inflation and medical advancements. In response to these trends, we increased both our current accident year loss ratio and prior year reserves in 2023. Given our shorter tail, we believe we are recognizing these trends earlier than the overall industry.

As previously noted, the number of data points and variables considered and the subjective process followed in establishing our loss reserve makes it impractical to isolate individual variables and demonstrate their impact on our estimate of loss reserves. However, to provide a better understanding of the potential variability in our reserves, we have modeled implied reserve ranges around our single point net reserve estimates for our various lines of business assuming different confidence levels. The ranges have been developed by aggregating the expected volatility of losses across partitions of our business to obtain a consolidated distribution of potential reserve outcomes. The aggregation of this data takes into consideration correlations among our geographic and specialty mix of business. The result of the correlation approach to aggregation is that the ranges are narrower than the sum of the ranges determined for each partition.

We have used this modeled statistical distribution to calculate an 80% and 60% confidence interval for the potential outcome of our consolidated net reserve for losses. The high and low end points of the distributions are as follows:

Any change in our estimate of net ultimate losses for prior years is reflected in net income (loss) in the period in which such changes are made. Due to the size of our consolidated reserve for losses and the large number of claims outstanding at any point in time, even a small percentage adjustment to our total reserve estimate could have a material effect on our results of operations for the period in which the adjustment is made, as was the case in 2023, 2022 and 2021.

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Loss Development by Line of Business

Professional Liability

Our professional liability line of business includes both our HCPL and Small Business Unit lines, with our HCPL line representing the largest component of our reserve. As a result of the higher severity environment, we saw our closed-with-indemnity-payment ratio (i.e., the number of suits closed with an indemnity or loss payment as compared to the total number of closed suits) for our claims increase from 28% in 2015 to 35% in 2023.

The following table presents additional information about the loss development for our professional liability line of business, excluding loss development for HCPL coverages assumed by the SPCs at Inova Re and Eastern Re. Furthermore, loss development for our professional liability line of business for the years ended December 31, 2023, 2022 and 2021 excludes the amortization of purchase accounting fair value adjustments:

•The loss environment in our HCPL line of business continues to be challenging in some jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. We are monitoring the impact that these trends have on our open case reserves and prior year development. Net unfavorable reserve development in 2023 principally related to accident years 2019 and 2020. Net unfavorable reserve development recognized in 2023 was driven by the strengthening of case reserves related to four large claims resulting in unfavorable development of $10.1 million in our HCPL line of business during the first quarter of 2023 and unfavorable development associated with our Small Business Unit. Further, we recognized unfavorable development in the fourth quarter of 2023 in NORCAL’s 2020 and prior accident year reserves which was entirely offset by favorable development recognized in NORCAL’s 2021 and 2022 accident year reserves since acquisition. These adjustments to NORCAL’s reserves had no impact to the segment’s net losses.

•Development recognized during 2022 principally related to accident years 2017, 2020 and 2021. Net favorable development recognized in 2022 included favorable development related to NORCAL's 2021 accident year. Net favorable prior accident year reserve development recognized in 2022 was partially offset by unfavorable development recognized in our HCPL line of business, excluding NORCAL, driven by higher than anticipated loss severity trends, which emerged primarily in the fourth quarter of 2022. In addition, we recognized favorable prior year reserve development of $9.0 million in 2022 related to the 2020 accident year associated with the remaining reduction to our previous COVID-19 IBNR reserve due to the fact that early first notices of potential claims did not turn into claims.

•Development recognized during 2021 principally related to accident years 2016 through 2020. We also recognized favorable prior year reserve development of $1.0 million associated with the reduction to our previous COVID-19 IBNR reserve.

•Not included in the table above, is $8.3 million, $10.8 million and $7.9 million of amortization of the purchase accounting fair value adjustment on NORCAL's assumed net reserve and amortization of the negative VOBA associated with NORCAL's DDR reserve which is recorded as a reduction to prior accident year net losses and loss adjustment expenses in 2023, 2022 and 2021, respectively.

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•Not included in the above table, as previously discussed, is $1.3 million and $0.7 million of unfavorable development recognized in 2023 and 2022, respectively, and $2.5 million of favorable development recognized during 2021 in our Segregated Portfolio Cell Reinsurance segment related to the HCPL coverages assumed by the SPCs at Inova Re and Eastern Re.

Medical Technology Liability

Our Medical Technology Liability line of business has not experienced the change in claims frequency previously described for HCPL. However, the nature of the risks insured and volatility of the loss experience in this line of business has produced more variable loss development, as presented in the following table:

•Approximately $4.5 million of the $4.0 million total net favorable development recognized in 2023 related to the 2020 through 2022 accident years. The development for the 2020 through 2022 accident years represents a 10.2% reduction to the ultimates established for those reserves at December 31, 2022.

•Approximately $6.3 million of the $5.0 million total net favorable development recognized in 2022 related to the 2018 through 2021 accident years. The development for the 2018 through 2021 accident years represents a 11.7% reduction to the ultimates established for those reserves at December 31, 2021.

•Approximately $7.6 million of the $8.1 million total net favorable development recognized in 2021 related to the 2015 through 2020 accident years. The development for the 2015 through 2020 accident years represents a 11.3% reduction to the ultimates established for those reserves at December 31, 2020.

•In 2023, 2022 and 2021 the development was largely attributable to favorable results from claims closed during the year. As time has elapsed we have recognized that actual loss experience has on average been better than estimated. We have been cautious in recognizing the improvement, but as claims have matured and claims are closed or have become more certain for the remaining open claims, we have revised reserve estimates. We believe the need for a cautious approach is required as outcomes are uncertain and results can be significantly affected by outcomes for a small number of cases.

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Workers' Compensation

Claims in our workers’ compensation line of business have historically closed at a faster rate than in our HCPL or Medical Technology Liability lines of business. This faster disposition rate, along with a lower net retention after the application of reinsurance, has resulted in less volatility in loss estimates on a net basis. However, a change in the number of individually-severe claims can create volatility in a given accident year. The following table presents additional information about the loss development for our workers' compensation line of business:

•In 2023, we recognized $9.3 million of net unfavorable development in our Workers' Compensation Insurance segment and $5.3 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business. The net unfavorable prior year reserve development in 2023 reflects higher than expected average claim costs primarily in the 2022 accident year and higher than expected loss experience primarily attributable to a large claim from the 1997 accident year.

•In 2022, we recognized $7.0 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business and $8.0 million of net favorable development in our Workers' Compensation Insurance segment.

•In 2021, we recognized $7.6 million of net favorable development in our Segregated Portfolio Cell Reinsurance segment related to workers' compensation business, and $7.1 million of net favorable development in our Workers' Compensation Insurance segment.

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Reinsurance

We use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer, to provide protection against losses in excess of policy limits and, in the case of risk sharing arrangements, to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay.

We make a determination of the amount of insurance risk we choose to retain based upon numerous factors, including our risk tolerance and the capital we have to support it, the price and availability of reinsurance, the volume of business, our level of experience with a particular set of exposures and our analysis of the potential underwriting results. We purchase excess of loss reinsurance to limit the amount of risk we retain and we do so from a number of companies to mitigate concentrations of credit risk. As of December 31, 2023, there is no reinsurer, on an individual basis, for which our recoverables for both paid and unpaid claims (net of amounts due to the reinsurer) and our prepaid balances are more than $65 million, in the aggregate. We utilize reinsurance brokers to assist us in the placement of these reinsurance programs and in the analysis of the credit quality of our reinsurers. The determination of which reinsurers we choose to do business with is based upon an evaluation of their then current financial strength, rating, stability and claims payment practices.

We evaluate each of our ceded reinsurance contracts at inception to confirm that there is sufficient risk transfer to allow the contract to be accounted for as reinsurance under current accounting guidance. At December 31, 2023, all ceded contracts were accounted for as risk transferring contracts.

Our receivable from reinsurers on unpaid losses and loss adjustment expenses represents our estimate of the amount of our reserve for losses that will be recoverable under our reinsurance programs. We base our estimate of funds recoverable upon our expectation of ultimate losses and the portion of those losses that we estimate to be allocable to reinsurers based upon the terms and conditions of our reinsurance agreements. Our assessment of the collectability of the recorded amounts receivable from reinsurers considers the payment history of the reinsurer, publicly available financial and rating agency data, our interpretation of the underlying contracts and policies and responses by reinsurers.

Given the uncertainty inherent in our estimates of losses and related amounts recoverable from reinsurers, these estimates may vary significantly from the ultimate outcome.

Under the terms of certain of our reinsurance agreements, the amount of premium that we cede to our reinsurers is based in part on the losses we recover under the agreements. Therefore, we make an estimate of premiums ceded under these reinsurance agreements subject to certain minimums and maximums. Any adjustments to our estimates of losses recoverable under our reinsurance agreements or the premiums owed under our agreements are reflected in current operations. Due to the size of our reinsurance balances, an adjustment to these estimates could have a material effect on our results of operations for the period in which the adjustment is made.

Our reinsurance receivables are exposed to credit losses but to date have not experienced any significant amount of credit losses. To partially mitigate our exposure to credit losses, reinsurance receivables totaling approximately $106.9 million were collateralized by letters of credit or funds withheld as of December 31, 2023. We measure expected credit losses on our reinsurance receivables on a collective basis when similar risk characteristics exist or on an individual basis if we determine a receivable does not share similar risk characteristics. We measure expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) at the consolidated level as our reinsurance receivables share similar risk characteristics including type of financial asset, type of industry and similar historical and expected credit loss patterns. We measure expected credit losses over the average contractual term of our reinsurance receivables utilizing a loss rate method. Historical internal credit loss experience is the basis for our assessment of expected credit losses; however, we may also consider historical credit loss information from external sources. We also consider reasonable and supportable forecasts of future economic conditions in our estimate of expected credit losses. Expected credit losses associated with our reinsurance receivables (related to both paid and unpaid losses) were nominal in amount as of December 31, 2023 and 2022. No reinsurance balances were written off for credit reasons during the years ended December 31, 2023 or 2022. Should our expected credit loss analysis or other facts or circumstances lead us to believe that any reinsurer may not meet its obligations to us, adjustments to the allowance for expected credit losses or to reinsurance receivables would be reflected in current operations. Such an adjustment has the potential to be material to the results of operations in the period in which it is recorded; however, we would not expect such an adjustment to have a material effect on our capital position or our liquidity. For further information on our allowance for expected credit losses related to our receivables from reinsurers see Note 1 of the Notes to Consolidated Financial Statements.

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Investment Valuations

We record the majority of our investments at fair value as shown in the table below. At December 31, 2023, the distribution of our investments based on GAAP fair value hierarchies (levels) was as follows:

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. All of our fixed maturity and equity investments are carried at fair value. The fair value of our short-term securities approximates the cost of the securities due to their short-term nature.

Because of the number of securities we own and the complexity of developing accurate fair values, we utilize multiple independent pricing services to assist us in establishing the fair value of individual securities. The pricing services provide fair values based on exchange-traded prices, if available. If an exchange-traded price is not available, the pricing services, if possible, provide a fair value that is based on multiple broker/dealer quotes or that has been developed using pricing models. Pricing models vary by asset class and utilize currently available market data for securities comparable to ours to estimate a fair value for our securities. The pricing services scrutinize market data for consistency with other relevant market information before including the data in the pricing models. The pricing services disclose the types of pricing models used and the inputs used for each asset class. Determining fair values using these pricing models requires the use of judgment to identify appropriate comparable securities and to choose a valuation methodology that is appropriate for the asset class and available data.

The pricing services provide a single value per instrument quoted. We review the values provided for reasonableness each quarter by comparing market yields generated by the supplied value versus market yields observed in the marketplace. We also compare yields indicated by the provided values to appropriate benchmark yields and review for values that are unchanged or that reflect an unanticipated variation as compared to prior period values. We utilize a primary pricing service for each security type and compare provided information for consistency with alternate pricing services, known market data and information from our own trades, considering both values and valuation trends. We also review weekly trades versus the prices supplied by the services. If a supplied value appears unreasonable, we discuss the valuation in question with the pricing service and make adjustments if deemed necessary. Historically our review has not resulted in any material changes to the values supplied by the pricing services. The pricing services do not provide a fair value unless an exchange-traded price or multiple observable inputs are available. As a result, the pricing services may provide a fair value for a security in some periods but not others, depending upon the level of recent market activity for the security or comparable securities.

Level 1 Investments

Fair values for a majority of our equity securities and portions of our short-term and convertible securities are determined using exchange-traded prices. There is little judgment involved when fair value is determined using an exchange-traded price. In accordance with GAAP, we classify securities valued using an exchange-traded price as Level 1 securities.

Level 2 Investments

Most fixed income securities do not trade daily; thus, exchange-traded prices are generally not available for these securities. However, market information (often referred to as observable inputs or market data, including but not limited to, last reported trade, non-binding broker quotes, bids, benchmark yield curves, issuer spreads, two-sided markets, benchmark securities, offers and recent data regarding assumed prepayment speeds, cash flow and loan performance data) is available for most of our fixed income securities. We determine fair value for a large portion of our fixed income securities using available market information. In accordance with GAAP, we classify securities valued based on multiple market observable inputs as Level 2 securities.

Level 3 Investments

When a pricing service does not provide a value for one of our fixed maturity securities, management estimates fair value using either a single non-binding broker quote or pricing models that utilize market based assumptions which have limited observable inputs. The process involves significant judgment in selecting the appropriate data and modeling techniques to use in the valuation process. In accordance with GAAP, we classify securities valued using limited observable inputs as Level 3 securities.

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Fair Values Not Categorized

We hold interests in certain investment funds, primarily LPs/LLCs, which measure fund assets at fair value on a recurring basis and provide us with a NAV for our interest. As a practical expedient, we consider the NAV provided to approximate the fair value of the interest. In accordance with GAAP, we do not categorize these investments within the fair value hierarchy.

Nonrecurring Fair Value Measurements

We measure the fair value of certain assets on a nonrecurring basis when events or changes in circumstances indicate that the carrying amount of the asset may not be recoverable. These assets include investments carried principally at cost, investments in tax credit partnerships, fixed assets, goodwill and other intangible assets. These assets would also include any equity method investments that do not provide a NAV. During the third quarter of 2023, we recognized a nonrecurring fair value measurement related to the goodwill in our Workers' Compensation Insurance reporting unit with a carrying value of $44.1 million prior to the fair value measurement. This nonrecurring fair value measurement resulted in the goodwill being written down to its implied fair value of zero resulting in an impairment of goodwill of $44.1 million (see following discussion under the heading "Goodwill / Intangibles"). The inputs used in the fair value measurement were non-observable and, as such, were categorized as a Level 3 valuation. We did not have any other assets or liabilities that were measured at fair value on a nonrecurring basis at December 31, 2023 or December 31, 2022.

Investments - Other Valuation Methodologies

Certain of our investments, in accordance with GAAP for the type of investment, are measured using methodologies other than fair value. At December 31, 2023, these investments represented approximately 3% of total investments, and are detailed in the following table. Additional information about these investments is provided in Note 2 and Note 3 of the Notes to Consolidated Financial Statements.

Impairments

We evaluate our available-for-sale investment securities, which at December 31, 2023 and December 31, 2022 consisted entirely of fixed maturity securities, on at least a quarterly basis for the purpose of determining whether declines in fair value below recorded cost basis represent an impairment loss. We consider a credit-related impairment loss to have occurred:

•if there is intent to sell the security;

•if it is more likely than not that the security will be required to be sold before full recovery of its amortized cost basis; or

•if the entire amortized basis of the security is not expected to be recovered.

The assessment of whether the amortized cost basis of a security is expected to be recovered requires management to make assumptions regarding various matters affecting future cash flows. The choice of assumptions is subjective and requires the use of judgment. Actual credit losses experienced in future periods may differ from management’s current estimates of those credit losses. Methodologies used to estimate the present value of expected cash flows are:

The estimate of expected cash flows is determined by projecting a recovery value and a recovery time frame and assessing whether further principal and interest will be received. We consider various factors in projecting recovery values and recovery time frames, including the following:

•third-party research and credit rating reports;

•the current credit standing of the issuer, including credit rating downgrades, whether before or after the balance sheet date;

•the extent to which the decline in fair value is attributable to credit risk specifically associated with the security or its issuer;

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•internal assessments and the assessments of external portfolio managers regarding specific circumstances surrounding an investment, which indicate the investment is more or less likely to recover its amortized cost than other investments with a similar structure;

•for asset-backed securities, the origination date of the underlying loans, the remaining average life, the probability that credit performance of the underlying loans will deteriorate in the future and our assessment of the quality of the collateral underlying the loan;

•failure of the issuer of the security to make scheduled interest or principal payments;

•any changes to the rating of the security by a rating agency;

•recoveries or additional declines in fair value subsequent to the balance sheet date;

•adverse legal or regulatory events;

•significant deterioration in the market environment that may affect the value of collateral (e.g., decline in real estate prices);

•significant deterioration in economic conditions; and

•disruption in the business model resulting from changes in technology or new entrants to the industry.

If deemed appropriate and necessary, a discounted cash flow analysis is performed to confirm whether a credit loss exists and, if so, the amount of the credit loss. We use the single best estimate approach for available-for-sale debt securities and consider all reasonably available data points, including industry analyses, credit ratings, expected defaults and the remaining payment terms of the debt security. For fixed rate available-for-sale debt securities, cash flows are discounted at the security's effective interest rate implicit in the security at the date of acquisition. If the available-for-sale debt security’s contractual interest rate varies based on subsequent changes in an independent factor, such as an index or rate, for example, the prime rate, the SOFR, or the U.S. Treasury bill weekly average, that security’s effective interest rate is calculated based on the factor as it changes over the life of the security. If we intend to sell a debt security or believe we will more likely than not be required to sell a debt security before the amortized cost basis is recovered, any existing allowance will be written off against the security's amortized cost basis, with any remaining difference between the debt security's amortized cost basis and fair value recognized as an impairment loss in earnings.

Exclusive of securities where there is an intent to sell or where it is not more likely than not that the security will be required to be sold before recovery of its amortized cost basis, impairment for debt securities is separated into a credit component and a non-credit component. The credit component of an impairment is the difference between the security’s amortized cost basis and the present value of its expected future cash flows, while the non-credit component is the remaining difference between the security’s fair value and the present value of expected future cash flows. An allowance for expected credit losses will be recorded for the expected credit losses through income and the non-credit component is recognized in OCI. The amount of impairment recognized is limited to the excess of the amortized cost over the fair value of the available-for-sale debt security.

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Deferred Taxes

Deferred federal income taxes arise from the recognition of temporary differences between the basis of assets and liabilities determined for financial reporting purposes and the basis determined for income tax purposes. Our temporary differences principally relate to our loss reserves, unearned and advanced premiums, DPAC, NOL and tax credit carryforwards, compensation related items, unrealized investment gains (losses) and basis differences on fixed assets, intangible assets and operating leases. Deferred tax assets and liabilities are measured using the enacted tax rates expected to be in effect when such benefits are realized. We review our deferred tax assets quarterly for impairment. If we determine that it is more likely than not that some or all of a deferred tax asset will not be realized, a valuation allowance is recorded to reduce the carrying value of the asset. In assessing the need for a valuation allowance, management is required to make certain judgments and assumptions about our future operations based on historical experience and information as of the measurement period regarding reversal of existing temporary differences, carryback capacity, future taxable income of the appropriate character (including its capital and operating characteristics) and tax planning strategies.

A significant portion of our deferred tax asset is related to unrealized losses on our fixed maturities due to the significant effect of fluctuations in interest rates in 2022 that continued through 2023. Any loss realized prior to recovery would require sufficient income of the appropriate character (i.e., capital gains), and in the appropriate timeframe, to realize the tax benefit. We believe that we have the intent and ability to hold these securities until their recovery. Our projected positive operating income, including the investment income generated from holding our debt securities until maturity, support our ability to implement this tax planning strategy.

A valuation allowance has been established against the deferred tax asset related to the NOL carryforwards for our U.K. operations and against a portion of the deferred tax asset related to our U.S. state NOL carryforwards. In addition, a valuation allowance was established against the net deferred tax asset of ProAssurance American Mutual, A Risk Retention Group. As a taxpayer separate from the consolidated group, this entity has experienced cumulative losses in recent years. Management concluded that it was more likely than not that these deferred tax assets will not be realized. We also established a valuation allowance in a prior year against the deferred tax assets of certain SPCs at our wholly owned Cayman Islands reinsurance subsidiary, Inova Re. Due to the cumulative losses incurred in recent years by these SPCs, management concluded that a valuation allowance was required. As of December 31, 2023, management concluded that the previously recorded valuation allowances were still required against the deferred tax assets related to the NOL carryforwards for our U.K. operations, against the deferred tax assets related to some of our U.S. state NOL carryforwards, the deferred tax assets of certain SPCs at Inova Re and against the net deferred tax asset of ProAssurance American Mutual, A Risk Retention Group. Management’s assessment of the need for these valuation allowances at December 31, 2023 included an analysis of the available sources of income. See further discussion on ProAssurance’s deferred tax assets in Note 5 of the Notes to Consolidated Financial Statements.

U.S. Tax Legislation

Coronavirus Aid, Relief and Economic Security Act

In response to COVID-19, the CARES Act was signed into law on March 27, 2020 and contains several provisions for corporations and eased certain deduction limitations originally imposed by the TCJA. See further discussion in Note 5 of the Notes to Consolidated Financial Statements. Temporary changes regarding NOL carryback provisions included in the CARES Act had a favorable impact on our liquidity, as we were able to carryback our 2019 and 2020 net operating losses to claim refunds (see discussion that follows in the Liquidity and Capital Resources and Financial Condition section under the heading "Taxes"). See further discussion in Note 5 of the Notes to Consolidated Financial Statements.

Unrecognized Tax Benefits

We evaluate tax positions taken on tax returns and recognize positions in our financial statements when it is more likely than not that we will sustain the position upon resolution with a taxing authority. If recognized, the benefit is measured as the largest amount of benefit that has a greater than 50% probability of being realized. We review uncertain tax positions each quarter, considering changes in facts and circumstances, such as changes in tax law, interactions with taxing authorities and developments in case law, and make adjustments as we consider necessary. Adjustments to our unrecognized tax benefits may affect our income tax expense, and settlement of uncertain tax positions may require the use of cash. Other than differences related to timing, no significant adjustments were considered necessary during 2023 or 2022. At December 31, 2023, our liability for unrecognized tax benefits approximated $4.8 million.

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Goodwill / Intangibles

In accordance with GAAP, goodwill and other indefinite lived intangible assets are tested for impairment annually or more frequently if circumstances indicate an impairment may have occurred. The date of our annual impairment testing is October 1. Impairment of goodwill is tested at the reporting unit level, which prior to the third quarter of 2023, was consistent with our reportable segments. As discussed in Note 16 of the Notes to Consolidated Financial Statements, we reorganized our segment reporting in the third quarter of 2023 to align with how our CODM currently oversees the business, allocates resources and evaluates operating performance. As a result of the segment reorganization, the Lloyd's Syndicates segment is no longer a separate operating segment; however, the Lloyd's Syndicates operation will remain a reporting unit for purposes of testing goodwill. Our reporting units are: Specialty P&C, Workers' Compensation Insurance, Segregated Portfolio Cell Reinsurance, Lloyd's Syndicates and Corporate. Of the five reporting units, only the Segregated Portfolio Cell Reinsurance reporting unit has goodwill at December 31, 2023.

During the third quarter of 2023, we recorded a goodwill impairment charge of $44.1 million, and the facts and circumstances that led to this impairment and how the fair value of each reporting unit was estimated, including the significant assumptions used and other details, are outlined in the following section.

Interim Impairment Assessments

As disclosed in our June 30, 2023 report on Form 10-Q, we performed a quantitative goodwill impairment assessment on our Workers' Compensation Insurance reporting unit as of June 30, 2023, due to market conditions impacting that reporting unit's actual and projected results along with a broader decline in our stock price that occurred for a sustained period of time during the second quarter of 2023.

The quantitative goodwill impairment test involves comparing the fair value of a reporting unit with its carrying value including goodwill. If the fair value of a reporting unit exceeds its carrying value, the reporting unit's goodwill is considered not to be impaired. However, if the carrying value of a reporting unit exceeds its fair value, an impairment loss is recorded in an amount equal to that excess. Any impairment charge recognized is limited to the amount of the respective reporting unit's allocated goodwill.

Determining the fair value of a reporting unit under the quantitative goodwill impairment test requires judgment and often involves the use of significant estimates and assumptions, including an assessment of external factors such as macroeconomic, industry and market conditions, as well as entity-specific factors, such as actual and planned financial performance. These estimates and assumptions could have a significant impact on whether or not an impairment charge is recognized and the magnitude of any such charge. To assist management in the process of determining any potential goodwill impairment, we may review and consider appraisals from accredited independent valuation firms. Estimates of fair value are primarily determined using discounted cash flows and market comparisons. These approaches involve significant estimates and assumptions, including projected future cash flows (including timing), discount rates reflecting the risks inherent in those future cash flows, perpetual growth rates, and selection of appropriate market comparable metrics and transactions.

As a result of the interim goodwill impairment assessment in the second quarter of 2023, management concluded that the fair value of the Workers' Compensation Insurance reporting unit exceeded the carrying value as of the testing date by approximately 3%; therefore, goodwill was not impaired during the second quarter of 2023.

Market conditions impacting actual and projected results of our Workers' Compensation Insurance reporting unit persisted into the third quarter of 2023. During the third quarter of 2023, we increased our full year current accident year loss ratio and recognized unfavorable prior accident year reserve development in our Workers' Compensation Insurance reporting unit, which reflected higher than expected loss trends observed in our average cost per claim which we attribute to increased medical costs driven by wage inflation and medical advancements. As a result, management performed an updated quantitative assessment of goodwill on our Workers' Compensation Insurance reporting unit as of September 30, 2023 using updated actual and projected results as well as marketplace data. The updated data impacted a number of key variables in our analysis including the determination of a higher discount rate and lower valuation multiples.

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For each of the interim impairment assessments performed in the second and third quarters of 2023, management estimated the fair value of the Workers' Compensation Insurance reporting unit using both an income approach and a market approach using marketplace data that was current at the time of each respective analysis based on the valuation methodologies and process for developing assumptions. The estimate of fair value derived from the income approach was based on the present value of expected future cash flows, including terminal value, utilizing a market-based weighted average cost of capital determined separately for each reporting unit. The estimate of fair value derived from the market approach was based on price to book multiple data. To corroborate the reporting unit's valuation, management performed a reconciliation of the estimate of the aggregate fair value of all reporting units to ProAssurance's market capitalization as of each testing date, including consideration of a control premium. The determination of fair value involved the use of significant estimates and assumptions, including revenue growth rates, combined ratios, capital requirements, tax rates, terminal growth rates, discount rates, comparable public companies and synergistic benefits available to market participants. In addition, management made certain judgments and assumptions in allocating shared assets and liabilities to individual reporting units to determine the carrying amount of each reporting unit.

The analysis during the third quarter of 2023 indicated impairment of the goodwill associated with our Workers' Compensation Insurance reporting unit and accordingly we recorded a $44.1 million charge to fully impair the goodwill in the third quarter.

In both our second and third quarter 2023 analyses, we also estimated the fair value of our Segregated Portfolio Cell Reinsurance reporting unit using the same approaches, which indicated that the fair value of the reporting unit significantly exceeded the carrying amount for each of the interim impairment assessments performed.

Management also performed impairment tests of indefinite lived intangible assets and certain of our definite lived intangible assets for which a triggering event was deemed to have occurred. Based upon these impairment tests, no impairment of our definite or indefinite lived intangible assets was identified at June 30, 2023 or September 30, 2023.

Annual Impairment Assessment

Subsequent to performing the interim impairment assessments previously discussed, we performed our annual goodwill impairment assessment as of October 1, 2023.

When testing goodwill for impairment on our annual test date, we have the option to first assess qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the estimated fair value of a reporting unit is less than its carrying amount. If we elect to perform a qualitative assessment and determine that an impairment is more likely than not, we are then required to perform a quantitative impairment test; otherwise, no further analysis is required. We also may elect not to perform the qualitative assessment and, instead, proceed directly to the quantitative impairment test.

For the most recent goodwill impairment test performed on October 1, 2023, we elected to perform a qualitative impairment test for our Segregated Portfolio Cell Reinsurance reporting unit. As of the last quantitative assessment as of September 30, 2023, the Segregated Portfolio Cell Reinsurance reporting unit had a significant excess of fair value over book value and based on current operations is expected to continue to do so; therefore, our annual impairment test for this reporting unit was performed qualitatively.

Performance of the qualitative goodwill impairment assessment requires judgment in identifying and considering the significance of relevant key factors, events and circumstances that affect the fair values of our reporting units. This requires consideration and assessment of external factors such as macroeconomic, industry, and market conditions, as well as entity-specific factors, such as our actual and planned financial performance. We also give consideration to the difference between the reporting unit's fair value and carrying value as of the most recent date that a fair value measurement was performed. If the results of the qualitative assessment conclude that it is not more likely than not that the fair value of a reporting unit exceeds its carrying value, additional quantitative impairment testing is performed.

In applying the qualitative approach, management considered macroeconomic factors, industry and market conditions, cost factors that could have a negative impact on the reporting unit, actual financial performance of the reporting unit versus expectations and management's future business expectations. As a result of the qualitative assessment, management concluded that it was not more likely than not that the fair value of the Segregated Portfolio Cell Reinsurance reporting unit was less than its carrying value as of the testing date; therefore, no further impairment testing was required. Management also performed impairment tests of our indefinite lived intangible assets which indicated no impairment as of October 1, 2023.

No goodwill impairment was recorded during the years ended December 31, 2022 or 2021.

Additional information regarding our goodwill and intangible assets is included in Note 1 and Note 6 of the Notes to Consolidated Financial Statements.

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Liquidity and Capital Resources and Financial Condition

Overview

ProAssurance Corporation is a holding company and is a legal entity separate and distinct from its subsidiaries. As a holding company, our principal source of external revenue is our investment revenues. In addition, dividends from our operating subsidiaries represent another source of funds for our obligations, including debt service and shareholder dividends, if declared. We also charge our core domestic operating subsidiaries within our Specialty P&C and Workers' Compensation Insurance segments a management fee based on the extent to which services are provided to the subsidiary and the amount of gross premium written by the subsidiary. At December 31, 2023, we held cash and liquid investments of approximately $65 million outside our insurance subsidiaries that were available for use without regulatory approval or other restriction. As of February 22, 2024, we also have an additional $125 million in permitted borrowings available under our Revolving Credit Agreement as well as the possibility of a $50 million accordion feature, if successfully subscribed, as discussed in this section under the heading "Debt."

During 2023, our operating subsidiaries paid dividends to us of approximately $31 million. Our insurance subsidiaries, in the aggregate, are permitted to pay dividends of approximately $145 million over the course of 2024 without prior approval of state insurance regulators. However, the payment of any dividend requires prior notice to the insurance regulator in the state of domicile, and the regulator may reduce or prevent the dividend if, in its judgment, payment of the dividend would have an adverse effect on the surplus of the insurance subsidiary. We make the decision to pay dividends from an insurance subsidiary based on the capital needs of that subsidiary and may pay less than the permitted dividend or may also request permission to pay an additional amount (an extraordinary dividend).

Cash Flows

Cash flows between periods compare as follows:

The principal components of our operating cash flows are the excess of premiums collected and net investment income over losses paid and operating costs, including income taxes. Timing delays exist between the collection of premiums and the payment of losses associated with the premiums. Premiums are generally collected within the twelve-month period after the policy is written, while our claim payments are generally paid over a more extended period of time. Likewise, timing delays exist between the payment of claims and the collection of any associated reinsurance recoveries.

The decrease in operating cash flows of $20.0 million in 2023 as compared to 2022 was primarily due to:

•A decrease in net premium receipts of $75.1 million primarily driven by our Specialty P&C segment due to the competitive market conditions on terms and pricing and an increase in cash paid to reinsurers primarily associated with our excess of loss reinsurance arrangements. In addition, the decrease in net premium receipts reflected our ceased participation in Syndicate 6131 for the 2022 underwriting year.

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The decrease in operating cash flows was partially offset by:

•A decrease in cash paid for operating expenses of $21.8 million driven by the prior year impact of the termination of deferred compensation arrangements assumed in the NORCAL acquisition during the first quarter of 2022 totaling approximately $13.2 million and, to a lesser extent, the receipt of cash collateral to secure the net present value of future cash flows associated with the Interest Rate Swaps of $4.0 million. See further discussion on the Interest Rate Swaps in Note 11 to the Notes to Consolidated Financial Statements. Furthermore, the decrease in cash paid for operating expenses reflected the prior year impact of one-time expenses of $3.9 million in our Specialty P&C segment. One-time expenses in 2022 were mainly comprised of one-time bonuses, employee severance charges and lease exit costs.

•Proceeds of $6.9 million associated with the sale of our ownership interest in the underwriting and operations entity associated with Syndicate 1729.

•A decrease in paid losses of $6.9 million driven by our Specialty P&C segment due to an increase in losses recoverable from reinsurers, partially offset by an increase in average indemnity paid per closed claim compared to the prior year period, as claim costs in our HCPL line of business are pressured by social inflation and higher than anticipated loss severity trends.

•The effect of a tax refund of approximately $11.7 million which we received in February 2023 (see additional discussion within this section under the heading "Taxes" that follows).

•An increase in cash received from investment income of $7.5 million driven by higher average book yields as we continue to reinvest at higher rates as our portfolio matures.

The remaining variance in operating cash flows in 2023 as compared to 2022 was composed of individually insignificant components.

We manage our investing cash flows to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated by our operations as discussed in this section under the heading "Investing Activities and Related Cash Flows."

Our financing cash flows are primarily comprised of share repurchases and dividend payments to our stockholders. See further discussion of our financing activities in this section under the heading "Financing Activities and Related Cash Flows."

Operating Activities and Related Cash Flows

Losses

The following table, known as the Analysis of Reserve Development, presents information over the preceding ten years regarding the payment of our losses as well as changes to (the development of) our estimates of losses during that time period. As noted in the table, we have completed various acquisitions over the ten year period which have affected original and re-estimated gross and net reserve balances as well as loss payments.

The table includes losses on both a direct and an assumed basis and is net of anticipated reinsurance recoverables. The gross liability for losses before reinsurance, as shown on the balance sheet, and the reconciliation of that gross liability to amounts net of reinsurance are reflected below the table. We do not discount our reserve for losses to present value. Information presented in the table is cumulative and, accordingly, each amount includes the effects of all changes in amounts for prior years. The table presents the development of our balance sheet reserve for losses; it does not present accident year or policy year development data. Conditions and trends that have affected the development of liabilities in the past may not necessarily occur in the future. Accordingly, it is not appropriate to extrapolate future redundancies or deficiencies based on this table.

The following may be helpful in understanding the Analysis of Reserve Development:

•The line entitled “Reserve for losses, undiscounted and net of reinsurance recoverables” reflects our reserve for losses and loss adjustment expense, less the receivables from reinsurers, each as reported in our Consolidated Balance Sheets at the end of each year (the Balance Sheet Reserves).

•The section entitled “Cumulative net paid, as of” reflects the cumulative amounts paid as of the end of each succeeding year with respect to the previously recorded Balance Sheet Reserves.

•The section entitled “Re-estimated net liability as of” reflects the re-estimated amount of the liability previously recorded as Balance Sheet Reserves that includes the cumulative amounts paid and an estimate of the remaining net liability based upon claims experience as of the end of each succeeding year (the Net Re-estimated Liability).

•The line entitled “Net cumulative redundancy (deficiency)” reflects the difference between the previously recorded Balance Sheet Reserve for each applicable year and the Net Re-estimated Liability relating thereto as of the end of the most recent fiscal year.

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See table notes on following page.

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Table Notes

•We have elected to present reserve history for acquired entities on a prospective basis in the table above; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Given the Lloyd's Syndicates line of business reserve is relatively small on a standalone basis as compared to our consolidated reserve, we have elected to exclude its reserve history for all periods presented in the table above, which is consistent with prior year; therefore, certain items will not agree to the following table which details activity in our net reserve for losses.

•Reserves for 2013 include gross and net reserves acquired in 2013 business combinations of $201.1 million and $126.0 million, respectively.

•Reserves for 2014 include gross and net reserves acquired in 2014 business combinations of $153.2 million and $139.5 million, respectively.

•Reserves for 2021 include gross and net reserves acquired in 2021 business combinations of $1.2 billion and $1.1 billion, respectively.

In each year reflected in the table, we have estimated our reserve for losses utilizing the management and actuarial processes discussed under the heading "Reserve for Losses and Loss Adjustment Expenses" in the Critical Accounting Estimates section. Factors that have contributed to the variation in loss development are primarily related to the extended period of time required to resolve professional liability claims and include the following:

•The HCPL legal environment deteriorated in the late 1990’s and severity began to increase at a greater pace than anticipated in our rates and reserve estimates. We addressed the adverse severity trends through increased rates, stricter underwriting and modifications to claims handling procedures, and reflected this adverse severity trend when we established our initial reserves for subsequent years.

•These adverse severity trends later moderated, with that moderation becoming more pronounced beginning in 2009. We were cautious in giving full recognition to indications that the pace of severity increase had slowed, however we gave measured recognition of the improved trend in our reserve estimates. The favorable development was most pronounced for years 2004 to 2008, as the initial reserves for these accident years were established prior to substantial indication that severity trends were moderating. We gave stronger recognition to the lower severity trend as time elapsed and a greater percentage of claims were closed.

•A general decline in claims frequency has also been a contributor to favorable loss development. A significant portion of our policies through 2003 were issued on an occurrence basis, and a smaller portion of our ongoing business results from the issuance of extended reporting endorsements which have occurrence-like exposure. As claims frequency declined, the number of reported claims related to these coverages was less than originally expected.

•Beginning in 2017, we identified potential higher severity trends in the broader HCPL industry. These trends were also reflected in increases in estimates of ultimate losses for open HCPL claims for earlier accident years, which resulted in a lower amount of favorable development recognized in 2018 and 2017 as compared to prior years.

•During 2019 the loss experience in our Specialty line of business in our Specialty P&C segment deteriorated further, particularly in regard to the reserves we established for a large national healthcare account that experienced losses far exceeding the assumptions we made when underwriting the account, beginning in 2016. As a result, we strengthened our Specialty reserves through the recognition of net unfavorable development on prior accident years and a higher current accident year net loss ratio in our Specialty P&C segment in 2019.

•The loss environment in our HCPL line of business in our Specialty P&C segment continues to be challenging in some jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. During the first quarter of 2023, we strengthened case reserves related to four large claims through the recognition of unfavorable development on prior accident years. Further, beginning in the second half of 2023, we observed higher than expected loss trends in our average cost per claim in our Workers' Compensation Insurance segment which we primarily attribute to increased medical costs driven by wage inflation and medical advancements. In response to these trends, we increased both our current accident year loss ratio and prior year reserves in our Workers' Compensation Insurance segment.

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Activity in our net reserve for losses during 2023, 2022 and 2021 is summarized below:

(1) Current year net losses and prior accident year development for the years ended December 31, 2023, 2022 and 2021 includes certain purchase accounting adjustments associated with our acquisition of NORCAL. See Note 7 of the Notes to Consolidated Financial Statements for additional information.

At December 31, 2023 our gross reserve for losses included case reserves of approximately $2.3 billion and IBNR reserves of approximately $1.2 billion. Our consolidated gross reserve for losses on a GAAP basis exceeds the combined gross reserves of our insurance subsidiaries on a statutory basis by approximately $0.2 billion, which is principally due to the portion of the GAAP reserve for losses that is reflected for statutory accounting purposes as unearned premiums. These unearned premiums are applicable to extended reporting endorsements (“tail” coverage) issued without a premium charge upon death, disability or retirement of an insured who meets certain qualifications.

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Reinsurance

Within our Specialty P&C segment, we use insurance and reinsurance (collectively, “reinsurance”) to provide capacity to write larger limits of liability, to provide reimbursement for losses incurred under the higher limit coverages we offer and to provide protection against losses in excess of policy limits. Within our Workers' Compensation Insurance segment, we use reinsurance to reduce our net liability on individual risks, to mitigate the effect of significant loss occurrences (including catastrophic events), to stabilize underwriting results and to increase underwriting capacity by decreasing leverage. In both our Specialty P&C and Workers' Compensation Insurance segments, we use reinsurance in risk sharing arrangements to align our objectives with those of our strategic business partners and to provide custom insurance solutions for large customer groups. The purchase of reinsurance does not relieve us from the ultimate risk on our policies; however, it does provide reimbursement for certain losses we pay. We pay our reinsurers a premium in exchange for reinsurance of the risk. In certain of our excess of loss arrangements, the premium due to the reinsurer is determined by the loss experience of the business reinsured, subject to certain minimum and maximum amounts. Until all loss amounts are known, we estimate the premium due to the reinsurer. Changes to the estimate of premium owed under reinsurance agreements related to prior periods are recorded in the period in which the change in estimate occurs and can have a significant effect on net premiums earned.

We offer alternative market solutions whereby we cede certain premiums from our Workers' Compensation Insurance and Specialty P&C segments to either the SPCs at Inova Re, one of our Cayman Islands reinsurance subsidiaries which is reported in our Segregated Portfolio Cell Reinsurance segment, or captive insurers unaffiliated with ProAssurance for two programs. The majority of these policies are reinsured to the SPCs at Inova Re, net of a ceding commission. See further discussion on our SPC operations in the Segment Results - Segregated Portfolio Cell Reinsurance section that follows. The alternative market workers' compensation policies are ceded from our Workers' Compensation Insurance segment to the SPCs under 100% quota share reinsurance agreements. The alternative market healthcare professional liability policies are ceded from our Specialty P&C segment to the SPCs under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. The portion of the risk that is not ceded to an SPC is retained in our Specialty P&C segment and may also be reinsured under our standard healthcare professional liability reinsurance program, depending on the policy limits provided. The remaining premium written in our alternative market business is 100% ceded to unaffiliated captive insurers.

Excess of Loss Reinsurance Agreements

We generally reinsure risks under treaties (our excess of loss reinsurance agreements) pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels, up to the maximum individual limits offered. Generally, these agreements are negotiated and renewed annually. Our HCPL and Medical Technology Liability treaties renew annually on October 1 and our Workers' Compensation treaty renews annually on May 1. Our HCPL and Medical Technology Liability treaties renewed October 1, 2023 at a higher rate than the previous treaties and retention of HCPL coverages in excess of $2 million increased to 9% to 9.5% from 0% to 5% of the next $24 million of risk; all other material terms were consistent with the expiring treaties. Our traditional Workers' Compensation treaty renewed May 1, 2023 at a higher rate than the previous treaty; all other material terms were consistent with the expiring treaty. The significant coverages provided by our current excess of loss reinsurance agreements are depicted in the following table.

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Excess of Loss Reinsurance Agreements

(1) Effective October 1, 2020, one prepaid limit reinstatement of $21M and a second limit reinstatement of up to $21M for the second layer, subject to reinstatement premium, which attaches after the first reinstatement has been completely exhausted. All limit reinstatements thereafter require no additional premium. Effective October 1, 2021, limits can be reinstated a maximum of four times.

(2) Prior to October 1, 2020, retention was $1M.

(3) Historically, retention has ranged from 0% to 32.5%.

(4) Historically, retention has ranged from $1M to $2M.

(5) Subject to a limit of $20M per individual claimant. If an individual loss were to exceed this level the Company would retain this excess exposure.

(6) Subject to an AAD where retention is 3.5% of subject earned premium in annual losses otherwise recoverable in excess of the $500K retention per loss occurrence.

Large HCPL risks that are above the limits of our basic reinsurance treaties may be reinsured on a facultative basis, whereby the reinsurer agrees to insure a particular risk up to a designated limit. We also have in place a number of risk sharing arrangements that apply to the first $1 million of losses for certain large healthcare systems and other insurance entities, as well as with certain insurance agencies that produce business for us.

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Other Reinsurance Arrangements

For the workers' compensation business ceded to Inova Re; each SPC has in place its own reinsurance arrangements, which are illustrated in the following table.

Segregated Portfolio Cell Reinsurance

(1) The attachment point is based on a percentage of written premium within individual cells, ranges from 85% to 94%, and varies by cell.

Each SPC has participants and the profit or loss of each cell accrues fully to these cell participants. As previously discussed, we participate in certain SPCs to a varying degree. Each SPC maintains a loss fund initially equal to the difference between premium assumed by the cell and the ceding commission. The external participants of each cell provide collateral to us, typically in the form of a letter of credit that is initially equal to the difference between the loss fund of the SPC (amount of funds available to pay losses after deduction of ceding commission) and the aggregate attachment point of the reinsurance. Over time, an SPC's retained profits are considered in the determination of the collateral amount required to be provided by the cell's external participants.

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Taxes

We are subject to the tax laws and regulations of the U.S., Cayman Islands and U.K. We file a consolidated U.S. federal income tax return that includes the parent company and its U.S. subsidiaries, except for ProAssurance American Mutual, A Risk Retention Group. Our filing obligations include a requirement to make quarterly payments of estimated taxes to the IRS using the corporate tax rate effective for the tax year. We did not make any quarterly estimated tax payments during the year ended December 31, 2023 as we expect NOL carryforwards to offset any income taxes due.

As a result of the CARES Act that was signed into law on March 27, 2020 we were permitted to carryback NOLs generated in tax years 2019 and 2020 for up to five years. See further discussion in the Critical Accounting Estimates section under the heading "U.S. Tax Legislation" and Note 5 of the Notes to Consolidated Financial Statements. We generated an NOL of approximately $33.3 million from the 2020 tax year that was carried back to the 2015 tax year that resulted in a tax refund of approximately $11.7 million which was received in February 2023. In addition, the CARES Act included the initial version of the ERC which was extended and expanded in December 2020 and March 2021. See further discussion of the ERC in Note 1 of the Notes to Consolidated Financial Statements. As an eligible employer under the provisions of the CARES Act, NORCAL filed a claim for a payroll tax refund of approximately $3.8 million during the second quarter of 2023, based on eligible wages paid during 2020.

As a result of the NORCAL acquisition, we have U.S. federal NOL carryforwards, which were approximately $32.3 million as of December 31, 2023. These NOL carryforwards are subject to limitation by Internal Revenue Code Section 382 and will begin to expire in 2035.

Investing Activities and Related Cash Flows

Our investments at December 31, 2023 and December 31, 2022 are comprised as follows:

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At December 31, 2023, 99% of our investments in available-for-sale fixed maturity securities were rated and the average rating was A+. The distribution of our investments in available-for-sale fixed maturity securities by rating were as follows:

A detailed listing of our investment holdings as of December 31, 2023 is located under the Financial Information heading on the Investor Relations page of our website which can be reached directly at https://investor.proassurance.com/financial-information/quarterly-investment-supplements/default.aspx or through links from the Investor Relations section of our website, investor.proassurance.com.

We manage our investments to ensure that we will have sufficient liquidity to meet our obligations, taking into consideration the timing of cash flows from our investments, including interest payments, dividends and principal payments, as well as the expected cash flows to be generated or used by our operations. In addition to the interest and dividends we will receive from our investments, we anticipate that between $70 million and $140 million of our portfolio will mature (or be paid down) each quarter over the next twelve months and become available, if needed, to meet our cash flow requirements. In response to higher severity trends and an increase in paid losses in our HCPL line of business and our Workers' Compensation Insurance segment, we have reduced the rate of reinvestment of these cash flows in order to allow for additional cash availability. The primary outflow of cash at our insurance subsidiaries is related to paid losses and operating costs, including income taxes. The payment of individual claims cannot be predicted with certainty; therefore, we rely upon the history of paid claims in estimating the timing of future claims payments with consideration given to current and anticipated industry trends and macroeconomic conditions. To the extent that we may have an unanticipated shortfall in cash, we may either liquidate securities or borrow funds under existing borrowing arrangements through our Revolving Credit Agreement and the FHLB system. As of February 22, 2024, $175 million could be made available for use through our Revolving Credit Agreement, as discussed in this section under the heading "Debt." Given the duration of our investments, we do not foresee a shortfall that would require us to meet operating cash needs through additional borrowings. Additional information regarding our Revolving Credit Agreement is detailed in Note 10 of the Notes to Consolidated Financial Statements.

At December 31, 2023, our FAL was comprised of investment securities, primarily available-for-sale fixed maturity securities, and a nominal amount of cash and cash equivalents deposited with Lloyd's which had a fair value of $20 million. During the second quarter of 2023, we received a return of approximately $4.1 million of cash from our FAL balances related to the settlement of our participation in the results of Syndicate 1729 and Syndicate 6131 for the 2020 underwriting year. Given that we decided to no longer participate in the results of Syndicate 1729 beginning with the 2024 underwriting year, we expect to receive an additional return of FAL in the future; however, the amount of which cannot be estimated at this time. Furthermore, we received proceeds of $6.8 million associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties during 2023. Additional information regarding our FAL is detailed in Note 3 of the Notes to Consolidated Financial Statements.

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Our investment portfolio continues to be primarily composed of high quality fixed income securities with approximately 93% of our fixed maturities being investment grade securities as determined by national rating agencies. The weighted average effective duration of our fixed maturity securities at December 31, 2023 was 3.25 years; the weighted average effective duration of our fixed maturity securities combined with our short-term securities was 3.05 years.

The carrying value and unfunded commitments for certain of our investments were as follows:

Investment fund LPs/LLCs are by nature less liquid and may involve more risk than other investments. We manage our risk through diversification of asset class and geographic location. At December 31, 2023, we had investments in 34 separate investment funds with a total carrying value of $276.1 million which represented approximately 6% of our total investments. Our investment fund LPs/LLCs generate earnings from trading portfolios, secured debt, debt securities, multi-strategy funds and private equity investments, and the performance of these LPs/LLCs is affected by the volatility of equity and credit markets. For our investments in LPs/LLCs, we record our allocable portion of the partnership operating income or loss as the results of the LPs/LLCs become available, typically following the end of a reporting period.

Financing Activities and Related Cash Flows

Treasury Shares

Treasury share activity for 2023, 2022 and 2021 was as follows:

We did not repurchase any common shares subsequent to December 31, 2023, and as of February 22, 2024, our remaining Board authorization was approximately $55.9 million.

ProAssurance Shareholder Dividends

Our Board declared cash dividends during 2023, 2022 and 2021 as follows:

Each dividend was paid in the month following the quarter in which it was declared. Cash dividends totaling $5 million were paid during the year ended December 31, 2023 and cash dividends totaling $11 million were paid during each of the years ended December 31, 2022 and 2021. In light of the price range in which our stock traded in the second quarter of 2023, the Board decided to suspend payment of a quarterly cash dividend. Instead, we used available capital to repurchase common shares pursuant to the existing share repurchase authorization. Any decision to pay future cash dividends is subject to the Board’s final determination after a comprehensive review of financial performance, future expectations and other factors deemed relevant by the Board.

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Debt

Our outstanding debt consisted of the following:

NORCAL Insurance Company, successor to NORCAL Mutual Insurance Company, issued Contribution Certificates, which bear interest at 3.0% annually and are due in 2031, to certain NORCAL policyholders in the conversion. The Contribution Certificates have a principal amount of $191 million and were recorded at their fair value of $175 million at the date of the NORCAL acquisition on May 5, 2021. The difference of $16 million between the recorded acquisition date fair value and the principal balance of the Contribution Certificates will be accreted utilizing the effective interest method over the term of the certificates of ten years as an increase to interest expense. Furthermore, interest payments are subject to deferral if we do not receive permission from the California Department of Insurance prior to payment. We received permission from the California Department of Insurance to pay the annual interest payment, which was paid in April 2023. There are no financial covenants associated with these certificates.

On April 28, 2023, we executed an amendment to the Revolving Credit Agreement, which extended the expiration from November 2024 to April 2028 and included an additional $125 million delayed draw Term Loan. The amended Revolving Credit Agreement may be used for general corporate purposes, including, but not limited to, short-term working capital, share repurchases as authorized by the Board and support for other activities. Our amended Revolving Credit Agreement permits borrowings of up to $250 million as well as the possibility of a $50 million accordion feature, if successfully subscribed. The Term Loan is available to be drawn up to $125 million during a five year period after closing, subject to customary borrowing conditions. We drew on the Revolving Credit Agreement and funded the Term Loan to refinance our Senior Notes in November 2023. We are in compliance with the financial covenants of the Revolving Credit Agreement.

Additional information regarding our debt is provided in Note 10 of the Notes to Consolidated Financial Statements.

To manage our exposure to interest rate risk due to variability in the base rate on borrowings under the amended Revolving Credit Agreement and Term Loan, we entered into two forward-starting interest rate swap agreements ("Interest Rate Swaps") on May 2, 2023, each with an effective date of December 29, 2023 and maturity date of March 31, 2028. Additional information regarding our Interest Rate Swaps is provided in Note 1 and Note 11 of the Notes to Consolidated Financial Statements.

Three of our insurance subsidiaries are members of an FHLB. Through membership, those subsidiaries have access to secured cash advances which can be used for liquidity purposes or other operational needs. In order for us to use FHLB proceeds, regulatory approvals may be required depending on the nature of the transaction. To date, those subsidiaries have not materially utilized their membership for borrowing purposes.

Contingent Consideration

Contingent consideration is measured at fair value on the date of acquisition and remeasured at fair value each subsequent reporting period. Fair value of a liability represents the price that would be paid to transfer the liability in an orderly transaction between market participants at the measurement date considering characteristics specific to the liability. The purchase consideration in the NORCAL acquisition included contingent consideration. NORCAL policyholders who elected to receive NORCAL stock and tender it to ProAssurance are eligible for a share of contingent consideration in an amount of up to approximately $84 million. As defined in the purchase agreement, the contingent consideration is dependent upon the after-tax development of NORCAL's ultimate net losses for accident years ended on or before December 31, 2020 determined as of December 31, 2023 by a mutually agreed upon independent actuarial consultant. This independent actuarial consultant has until June 30, 2024 to complete their estimate.

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Given the contingent consideration associated with the NORCAL acquisition is dependent upon the after-tax development of NORCAL's ultimate net losses between December 31, 2020 and December 31, 2023, we bifurcate changes in the contingent consideration each period between fair value changes and, if applicable, changes in estimates of NORCAL's ultimate net losses for accident years 2020 and prior. See further discussion regarding our estimates of ultimate net losses in this section under the heading "Reserve for Losses and Loss Adjustment Expenses" in the Critical Accounting Estimates section. Changes in the contingent consideration related to fair value are recognized in earnings as a component of net investment gains (losses) and changes in the contingent consideration related to changes in estimates of NORCAL's ultimate net losses for accident years 2020 and prior are recognized in earnings as component of operating expenses.

As of December 31, 2023 and December 31, 2022, the contingent consideration liability was $6.5 million and $15.0 million, respectively, carried at fair value utilizing a stochastic model (see Note 2 of the Notes to Consolidated Financial Statements). This estimate of fair value does not guarantee nor suggest that contingent consideration will ultimately be paid, and any amounts ultimately paid by the Company may be greater than or less than the $6.5 million current fair value estimate. As of December 31, 2023, our current analysis of NORCAL's reserves related to accident years 2020 and prior suggests that no contingent consideration will be due; however, the actual amount due to be paid, if any, will be determined based on an analysis to be performed by an independent actuary, as previously discussed. This remaining uncertainty is a significant component in the determination of the fair value of the liability as of December 31, 2023. See further discussion around the contingent consideration and the NORCAL acquisition in Note 2 and Note 8 of the Notes to Consolidated Financial Statements.

During the years ended December 31, 2023 and 2022, we recorded an $8.5 million and $9.0 million decrease to the contingent consideration liability, respectively. The decrease recorded during the year ended December 31, 2023 was comprised of $5.0 million related to the remeasurement of the liability to fair value and $3.5 million related to the impact of unfavorable development recognized in 2023 on NORCAL's reserves related to accident years 2020 and prior. The entire decrease in the liability of $9.0 million during the year ended December 31, 2022 related to the remeasurement of the liability to fair value. See further discussion that follows under the heading "Results of Operations."

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Results of Operations - Year Ended December 31, 2023 Compared to Year Ended December 31, 2022

Selected consolidated financial data for each period is summarized in the table below.

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Executive Summary of Operations

The following sections provide an overview of our consolidated and segment results of operations for the year ended December 31, 2023 as compared to the year ended December 31, 2022. See the Segment Results sections that follow for additional information regarding each segment's results. For a full discussion of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021, please refer to Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" section of ProAssurance's December 31, 2022 report on Form 10-K. Any significant retrospective revisions in the presentation of the changes in the financial condition, results of operations and cash flows for the year ended December 31, 2022 as compared to the year ended December 31, 2021 as reported in ProAssurance's December 31, 2022 report on Form 10-K are located in this report under the section that follows titled "Results of Operations - Year Ended December 31, 2022 Compared to Year Ended December 31, 2021."

Revenues

The following table shows our consolidated and segment net premiums earned:

For the year ended December 31, 2023, consolidated net premiums decreased $52.2 million as compared to 2022.

•For our Specialty P&C segment, net premiums earned decreased during 2023 as compared to 2022 due to the pro rata effect of a decrease in the volume of premium written during the preceding twelve months primarily due to competitive market conditions as well as our process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies in 2022, which impacted earned premium in 2023.

•For our Workers' Compensation Insurance segment, net premiums earned decreased in 2023 due to the continuation of competitive market conditions and reinsurance reinstatement premium of $1.6 million recorded in 2023 related to a reserve increase on a prior year reinsured claim, partially offset by an increase in the carried EBUB estimate of $2.9 million in 2023 as compared to $1.5 million in 2022.

•Net premiums earned in our Segregated Portfolio Cell Reinsurance segment decreased during 2023 due to the continuation of competitive workers' compensation market conditions and a decrease in audit premium billed to policyholders.

The following table shows our consolidated net investment result:

The increase in our consolidated net investment income for the year ended December 31, 2023 as compared to 2022 reflected higher average book yields as we continue to reinvest at higher rates as our portfolio matures. Our equity in earnings of unconsolidated subsidiaries increased in 2023 as compared to 2022 driven by lower amortization of tax credit operating losses, partially offset by the performance of several LP/LLCs, which reflected lower market valuations during the fourth quarter of 2022 and first quarter of 2023.

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The following table shows our total consolidated net investment gains (losses):

For the year ended December 31, 2023, we recognized $3.1 million of credit-related impairment losses in earnings. We did not recognize any non-credit impairment losses in OCI during the year ended December 31, 2023. The credit-related impairment losses recognized during the year ended December 31, 2023 related to a mortgage-backed security and two corporate bonds in the financial sector. For the year ended December 31, 2022, we recognized credit-related impairment losses in earnings of $1.8 million and a nominal amount of non-credit impairment losses in OCI. The credit-related and non-credit impairment losses in OCI during the year ended December 31, 2022 related to a corporate bond in the consumer sector as well as certain mortgage-backed and other asset backed securities. Additional information regarding investment impairment losses is provided in Note 3 of the Notes to Consolidated Financial Statements.

We recognized $16.9 million of other net investment gains for the year ended December 31, 2023 driven by unrealized holding gains resulting from changes in the fair value of our convertible securities and equity investments, to a lesser extent, the remeasurement of the contingent consideration liability. We recognized $31.4 million of other net investment losses for the year ended December 31, 2022 driven by unrealized holding losses resulting from changes in the fair value of our equity investments and convertible securities and, to a lesser extent, realized losses from the sale of equity investments.

Consolidated other income for the year ended December 31, 2023 as compared to 2022 was comprised as follows:

Excluding the foreign currency exchange rate gains (losses), other income increased for the year ended December 31, 2023 as compared to 2022 driven by proceeds of $6.9 million received in 2023 associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties.

Foreign currency exchange rate changes are primarily related to foreign currency denominated loss reserves associated with premium assumed from an international medical professional liability insured in our Specialty P&C segment. Our participation in this program has grown in recent years which has led to greater volatility in our results of operations even with nominal movements in exchange rates given the size of the reserve. We mitigate foreign exchange exposure by generally matching the currency and duration of associated investments to the corresponding loss reserves. In accordance with GAAP, the impact on the market value of available-for-sale fixed maturities due to changes in foreign currency exchange rates is reflected as part of OCI. Conversely, the impact of changes in foreign currency exchange rates on loss reserves is reflected through net income (loss) as a component of other income. The effect of exchange rate changes on foreign currency denominated loss reserves are reported in our Corporate segment to be consistent with the reporting of the foreign currency denominated invested assets and associated investment income.

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Expenses

The following table shows our consolidated and segment net loss ratios and net prior accident year reserve development.

The primary drivers of the change in our consolidated current accident year net loss ratio for the year ended December 31, 2023 as compared to 2022 were as follows:

•The increase in the current accident year net loss ratio in our Workers' Compensation Insurance segment for the year ended December 31, 2023 as compared to 2022 was driven by higher than expected loss trends observed in our average cost per claim which we primarily attribute to increased medical costs driven by wage inflation and medical advancements. The increase also reflected the impact of reinsurance reinstatement premium, an increase in estimated losses within the AAD and, to a lesser extent, higher ULAE. See previous discussion on reinstatement premium under the heading "Revenues."

•Our current accident year net loss ratio in our Specialty P&C and Segregated Portfolio Cell Reinsurance segments remained relatively unchanged for 2023 as compared to 2022.

•As a result of our acquisition of NORCAL, our consolidated current accident year net loss ratio in 2022 was impacted by the purchase accounting amortization of the negative VOBA associated with NORCAL's assumed unearned premium of $4.9 million, which was recorded as a reduction to current accident year net losses. As of June 30, 2022, the negative VOBA was fully amortized which resulted in a 0.5 percentage point increase in 2023 as compared 2022.

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In 2023, our consolidated calendar year net loss ratio was higher than our consolidated current accident year net loss ratio due to the recognition of net unfavorable prior year reserve development, as shown in the previous table. For 2022, our consolidated calendar year net loss ratio was lower than our consolidated current accident year net loss ratio due to the recognition of net favorable prior year reserve development, as shown in the previous table. The following table shows the components of our consolidated net prior accident year reserve development:

•Specialty P&C: The loss environment in our HCPL line of business continues to be challenging in some jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. We are monitoring the impact that these trends have on our open case reserves and prior year development. Net unfavorable reserve development was driven by the strengthening of case reserves related to four large claims in our HCPL line of business and unfavorable development associated with our Lloyd’s Syndicates operations, partially offset by net favorable development in other lines of business, predominately in our Medical Technology Liability line of business.

The contingent consideration associated with the NORCAL acquisition is dependent upon the after-tax development of NORCAL’s 2020 and prior accident year reserves from December 31, 2020 to December 31, 2023. In the fourth quarter of 2023, we recognized unfavorable development in NORCAL’s 2020 and prior accident year reserves which was entirely offset by favorable development recognized in NORCAL’s 2021 and 2022 accident year reserves since acquisition. While these adjustments to NORCAL’s reserves had no impact to our Specialty P&C segment’s net losses or net loss ratio, they contributed to the decrease in the fair value of the contingent consideration liability of $3.5 million in 2023 which was recorded as an offset to operating expenses in the Specialty P&C segment. See additional discussion on the Contingent Consideration in the Critical Accounting Estimates section under the heading "Contingent Consideration."

•Workers' Compensation Insurance: Net unfavorable development in 2023 reflected higher than expected loss trends observed in our average cost per claim, primarily in the 2022 accident year. We are monitoring the impact that these trends have on our open case reserves and prior year development. Net unfavorable development in 2023 also reflected higher than expected loss experience attributable to one large claim from the 1997 accident year.

•Segregated Portfolio Cell Reinsurance: Net favorable development in 2023 reflected overall favorable trends in claim closing patterns related to the workers' compensation business, primarily in accident years 2016 through 2021.

See the Segment Results sections that follow for additional information regarding each segment's reserve development.

Our consolidated and segment underwriting expense ratios were as follows:

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The change in our consolidated underwriting expense ratio for the year ended December 31, 2023 as compared to 2022 was primarily attributable to the following:

•Excluding the impact of the items specifically identified in the table above, our consolidated underwriting expense ratio increased by 1.6 percentage points in 2023 as compared to 2022 primarily driven by an increase in operating expenses in our Specialty P&C segment due to an increase in compensation-related expenses and, to a lesser extent, travel-related expenses, partially offset by a decrease in amounts accrued for performance-related incentive plans across all our operating segments.

•As shown in the previous table, our consolidated underwriting expense ratio for 2023 reflected the impact of the change in net premiums earned, excluding tail premium, in relation to the corresponding DPAC amortization resulting in a 0.4 percentage point increase in our ratio as compared to 2022 driven by the effect of reinsurance reinstatement premium recognized during the fourth quarter of 2023 in our Workers' Compensation Insurance segment (see previous discussion under the heading "Revenues").

•As shown in the previous table, our consolidated underwriting expense ratios for 2023 reflected the impact of the change in premium earned from tail policies as there is typically minimal associated acquisition costs.

•As shown in the previous table, our change in our consolidated underwriting expense ratio for 2023 also reflected the impact of a payroll tax refund of $3.8 million recognized in the first quarter of 2023 as a reduction to operating expenses in our Specialty P&C segment related to the employee retention credit available to us under the CARES Act, which resulted in a 0.4 percentage point decrease in the current period ratio. See additional discussion on the ERC in Note 1 of the Notes to Consolidated Financial Statements and previous discussion in the Liquidity section under the heading "Taxes."

•As shown in the previous table, the consolidated underwriting expense ratio for 2023 also reflects the prior year impact of one-time expenses of $3.9 million incurred in 2022 and accounted for a 0.4 percentage point decrease to our 2023 ratio. One-time expenses were mainly comprised of one-time bonuses, accelerated depreciation associated with a decommissioned IT system, employee severance charges and lease exit costs in our Specialty P&C segment.

•As shown in the previous table, our consolidated underwriting expense ratio for 2023 reflected the impact of the remeasurement of the contingent consideration liability associated with the NORCAL acquisition, which resulted in a 0.4 percentage point decrease in our 2023 ratio. As previously discussed, we recorded a reduction to operating expenses of $3.5 million related to the remeasurement of the contingent consideration liability associated with the NORCAL acquisition due to unfavorable development recognized on NORCAL's 2020 and prior accident year reserves in our Specialty P&C segment. See additional discussion on the Contingent Consideration in the Critical Accounting Estimates section under the heading "Contingent Consideration."

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Taxes

Our consolidated effective tax rates for the years ended December 31, 2023 and 2022 were as follows:

We recognized an income tax benefit of $0.5 million and $5.8 million in 2023 and 2022, respectively. Our effective tax rate for the year ended December 31, 2023 was different from the statutory federal income tax rate of 21% primarily due to a $44.1 million goodwill impairment recognized in relation to the Workers' Compensation Insurance reporting unit during the third quarter of 2023, all of which is non-deductible. See further discussion on this goodwill impairment in Note 6 of the Notes to Consolidated Financial Statements. Our effective tax rate for the year ended December 31, 2022 differed from the statutory federal income tax rate of 21% primarily due to the benefit recognized from the tax credits transferred to us from our tax credit partnership investments. See further information on other notable items impacting our effective tax rate for the years ended December 31, 2023 and 2022 in the Segment Results - Corporate section that follows under the heading "Taxes."

Operating Ratio

Our operating ratio is our combined ratio, less our investment income ratio. This ratio provides the combined effect of underwriting profitability and investment income. Our operating ratio for the years ended December 31, 2023 and 2022 was as follows:

The primary drivers of the change in our operating ratio were as follows:

Excluding the impact of the items specifically identified in the table above, our operating ratio in 2023 increased 3.3 percentage points as compared to 2022 driven by an increase in the consolidated combined ratio, the components of which are discussed in this section under the heading "Expenses" and further discussion in our Segment Operating Results sections that follow.

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Non-GAAP Financial Measures

Non-GAAP Operating Income (Loss)

Non-GAAP operating income (loss) is a financial measure that is widely used to evaluate performance within the insurance sector. In calculating Non-GAAP operating income (loss), we have excluded the effects of the items listed in the following table that do not reflect normal results. We believe Non-GAAP operating income (loss) presents a useful view of the performance of our insurance operations; however, it should be considered in conjunction with net income (loss) computed in accordance with GAAP.

The following table is a reconciliation of net income (loss) to Non-GAAP operating income (loss):

(1) Net investment gains (losses) in 2023 and 2022 include gains of $5.0 million and $9.0 million, respectively, related to the change in the fair value of contingent consideration issued in connection with the NORCAL acquisition. We have excluded these adjustments as they do not reflect normal operating results. See further discussion around the contingent consideration in Note 2 and Note 8 of the Notes to Consolidated Financial Statements and discussion on our accounting policy in the Critical Accounting Estimates section under the heading "Contingent Consideration."

(2) Net investment gains (losses) on investments related to SPCs are recognized in our Segregated Portfolio Cell Reinsurance segment. SPC results, including any net investment gain or loss, that are attributable to external cell participants are reflected in the SPC dividend expense (income). To be consistent with our exclusion of net investment gains (losses) recognized in earnings, we are excluding the portion of net investment gains (losses) that is included in the SPC dividend expense (income) which is attributable to the external cell participants.

(3) Transaction-related costs associated with our acquisition of NORCAL. We are excluding these costs as they do not reflect normal operating results and are unique and non-recurring in nature.

(4) Foreign currency exchange rate gains (losses) relate to the impact of foreign exchange rate movements on foreign currency denominated loss reserves predominately associated with premium assumed from an international medical professional liability insured in our Specialty P&C segment. Our participation in this program has grown in recent years which has led to greater volatility in our results of operations even with nominal movements in exchange rates given the size of the reserve. We mitigate foreign exchange rate exposure on our Consolidated Balance Sheet by generally matching the currency and duration of associated investments to the corresponding loss reserves. In accordance with GAAP, the impact on the market value of available-for-sale fixed maturities due to changes in foreign currency exchange rates is reflected as a part of OCI. Conversely, the impact of changes in foreign currency exchange rates on loss reserves is reflected through net income (loss) as a component of other income. Therefore, we believe foreign currency exchange rate gains (losses) in our Consolidated Statements of Income and Comprehensive Income in isolation are not indicative of our operating performance.

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(5) Proceeds associated with the sale of our remaining ownership interest in the underwriting and operations entity associated with Syndicate 1729 to unrelated third parties recognized in other income in our Corporate segment. We are excluding these costs as they do not reflect normal operating results and are unique and non-recurring in nature.

(6) The 21% rate is the statutory tax rate associated with the taxable or tax deductible items listed above. Our statutory tax rate was applied to these items in calculating net income (loss), excluding the 2023 goodwill impairment which is not tax deductible. In addition, the 2023 and 2022 gains related to the change in the fair value of contingent consideration are non-taxable and therefore had no associated income tax impact. The taxes associated with the net investment gains (losses) related to SPCs in our Segregated Portfolio Cell Reinsurance segment are paid by the individual SPCs and are not included in our consolidated tax provision or net income (loss); therefore, both the net investment gains (losses) from our Segregated Portfolio Cell Reinsurance segment and the adjustment to exclude the portion of net investment gains (losses) included in the SPC dividend expense (income) in the table above are not tax effected.

Non-GAAP Operating ROE

Non-GAAP operating ROE is a financial measure that is calculated as Non-GAAP operating income (loss) for the period divided by the average of beginning and ending total GAAP shareholders’ equity. As previously discussed, in calculating Non-GAAP operating income (loss), we have excluded the effects of certain items that do not reflect normal results. Non-GAAP operating ROE measures the overall after-tax profitability of our insurance operations and shows how efficiently capital is being used; however, it should be considered in conjunction with ROE computed in accordance with GAAP. The following table is a reconciliation of ROE to Non-GAAP operating ROE for the years ended December 31, 2023 and 2022:

Non-GAAP operating ROE in 2023 decreased by 2.5 percentage points as compared to 2022 driven by unfavorable prior accident year reserve development and, to a lesser extent, an increase in the current accident year net loss ratio in our Workers' Compensation Insurance segment, partially offset by an increase in investment income due to higher average book yields as we continue to reinvest at higher rates as our portfolio matures. See previous discussions in this section under the headings "Executive Summary of Operations" and further discussion in our Segment Operating Results sections that follow.

Non-GAAP Adjusted Book Value per Share

Book value per share is calculated as total GAAP shareholders’ equity divided by the total number of common shares outstanding at the balance sheet date. This ratio measures the net worth of the Company to shareholders on a per share basis.

Non-GAAP adjusted book value per share is a Non-GAAP measure widely used within the insurance sector and is calculated as shareholders’ equity, excluding AOCI, divided by the total number of common shares outstanding at the balance sheet date. This Non-GAAP calculation measures the net worth of the Company to shareholders on a per share basis excluding AOCI to eliminate the temporary and potentially significant effects of fluctuations in interest rates on our fixed income portfolio; however, it should be considered in conjunction with book value per share computed in accordance with GAAP. The increase in interest rates led to significant unrealized holding losses on our available-for-sale fixed maturity investments resulting in volatility in AOCI in 2022 and 2023. See Note 12 of the Notes to Consolidated Financial Statements for additional information.

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The following table is a reconciliation of our book value per share to Non-GAAP adjusted book value per share at December 31, 2023 and December 31, 2022:

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Segment Results - Specialty Property & Casualty

Our Specialty P&C segment focuses on professional liability insurance and medical technology liability insurance as discussed in Note 16 of the Notes to Consolidated Financial Statements. As previously discussed under the heading "ProAssurance Overview," we reorganized our segment reporting in the third quarter of 2023. As a result, the underwriting results from our participation in the results of Syndicate 1729 and Syndicate 6131 at Lloyd's of London which were previously reported in our Lloyd’s Syndicates segment are now reported in our Specialty P&C segment. We normally report results from our involvement in Lloyd's Syndicates on a quarter lag, except when information is available that is material to the current period. All prior period segment information has been recast to conform to the current period presentation and the segment reorganization had no impact on previously reported consolidated financial results. See further information regarding the segment reorganization in Note 16 of the Notes to Consolidated Financial Statements.

Segment results reflected pre-tax underwriting profit or loss from these insurance lines and included the amortization of certain purchase accounting adjustments. Segment results for the year ended December 31, 2022 exclude transaction-related costs associated with our acquisition of NORCAL as we do not consider these costs in assessing the financial performance of the segment. We did not incur any transaction-related costs during the year ended December 31, 2023. Segment results included the following:

Premiums Written

Changes in our premium volume within our Specialty P&C segment are generally driven by three primary factors: (1) the amount of new business written, (2) our retention of existing business and (3) the premium charged for business that is renewed, which is affected by rates charged and by the amount and type of coverage an insured chooses to purchase. In addition, premium volume may periodically be affected by shifts in the timing of renewals between periods.

The medical professional liability market, which accounts for a majority of the revenues in this segment, remains challenging as physicians continue joining hospitals or larger group practices and, therefore, are no longer purchasing individual or group policies in the standard market. In addition, some competitors have chosen to compete primarily on price. Both factors may impact our ability to write new business and retain existing business. Furthermore, the insurance and reinsurance markets have historically been cyclical, characterized by extended periods of intense price competition and other periods of reduced capacity. The medical professional liability market has been particularly affected by these cycles. Underwriting cycles are driven, among other reasons, by excess capacity available to compete for the business. Changes in the frequency and severity of losses may also affect the cycles of the insurance and reinsurance markets significantly. During “soft markets” where price competition is high and underwriting profits are poor, growth and retention of business become challenging which may result in reduced premium volumes.

Gross, ceded and net premiums written were as follows:

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Gross Premiums Written

Gross premiums written by component were as follows:

(1) Standard Physician premium was our greatest source of premium revenues in 2023 and 2022 and is comprised of twelve month term policies and, for 2022, three month term policies. The decrease in Standard Physician premium for 2023 as compared to 2022 was driven by retention losses and, to a lesser extent, the impact of the conversion of three month term policies to twelve month term policies in the prior year period, partially offset by an increase in renewal pricing and new business written, including the addition of six policies totaling $9.1 million. Retention losses during 2023 generally reflect our pursuit of rate adequacy in a competitive market where other carriers may not have the same objectives, appreciate the rate need, or are attempting to gain market share despite near term underwriting losses (see additional discussion in Part I Item 1. Business under the heading "Competition"). Renewal pricing increases during 2023 reflect the rising loss cost environment and new business written reflects the competitive market conditions.

(2) Custom Physician premium includes large physician groups, multi-state physician groups and non-standard physicians and is written primarily on an excess and surplus lines basis. The increase in Custom Physician premium in 2023 as compared to 2022 was driven by new business written, including the addition of five policies totaling $6.2 million during the 2023 and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Renewal pricing increases for 2023 reflect pricing actions taken in response to a rising loss cost environment and new business written reflects the competitive market conditions. The retention losses in our Custom Physician book in 2023 reflects our focus on underwriting discipline, the loss of a $2.2 million policy due to price competition and the loss of a $2.8 million policy due to the insured moving to a captive arrangement.

(3) Hospitals and Facilities premium (which includes hospitals, surgery centers and miscellaneous medical facilities) increased in 2023 as compared to 2022 driven by new business written, including the addition of two policies totaling $6.9 million and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Renewal pricing increases in 2023 reflect rate increases and contract modifications that we believe are appropriate given the current loss environment and new business written reflects the competitive market conditions. Retention losses in 2023 were largely attributable to the loss of a $4.6 million policy due to the insured entering into a captive arrangement during the first quarter of 2023, which resulted in a decrease to our Specialty retention rate of 3.0 percentage points.

(4) Senior Care premium includes facilities specializing in long term residential care primarily for the elderly ranging from independent living through skilled nursing. Our Senior Care premium increased in 2023 as compared to 2022 driven by new business written and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses.

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(5) We offer custom alternative risk solutions including assumed reinsurance. The increase in premium in 2023 reflected an increase in premiums assumed on a quota share basis through a strategic partnership in place since 2016 with an international medical professional liability insurer and, to a lesser extent, an increase in premiums assumed through a reinsurance arrangement with a hospital captive insurance company.

(6) Our Small Business Unit is comprised of premium associated with podiatrists, legal professionals, dentists and chiropractors. Our Small Business Unit premium decreased in 2023 as compared to 2022 driven by retention losses, partially offset by an increase in renewal pricing and, to a lesser extent, new business written. The increase in renewal pricing in 2023 was primarily the result of an increase in the rate charged for certain renewed policies in select states.

(7) We offer extended reporting endorsement or "tail" coverage to insureds who discontinue their claims-made coverage with us, and we also periodically offer tail coverage through stand-alone policies. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and generally are not cancellable. The amount of tail coverage premium written can vary significantly from period to period.

(8) Our Medical Technology Liability business is marketed throughout the U.S.; coverage is offered on a primary and excess basis, within specified limits, to manufacturers and distributors of medical technology and life sciences products including entities conducting human clinical trials. In addition to the previously listed factors that affect our premium volume, our Medical Technology Liability premium is also impacted by the sales volume of insureds. Our Medical Technology Liability premium increased in 2023 as compared to 2022 driven by new business written, timing differences primarily related to the prior year renewal of one policy and, to a lesser extent, an increase in renewal pricing, partially offset by retention losses. Renewal pricing increases in 2023 are primarily due to changes in the sales volume and changes in exposure of certain insureds. Retention losses in 2023 are primarily attributable to insureds no longer needing coverage, insureds no longer in business, an increase in competition on terms and pricing, cancellation for non-payment, as well as merger activity within the industry.

(9) Our Lloyd's Syndicates business includes the results from our participation in Syndicate 1729 and Syndicate 6131 at Lloyd's of London. For each of the 2023 and 2022 underwriting years our participation in the results of Syndicate 1729 is approximately 5%. Effective January 1, 2022, Syndicate 6131 ceased underwriting on a quota share basis with Syndicate 1729. Due to the quarter lag, our ceased participation in Syndicate 6131 was not reflected in our results until the second quarter of 2022. Our Lloyd’s Syndicates premium decreased during 2023 as compared to 2022 driven by our ceased participation in Syndicate 6131 for the 2022 underwriting year, partially offset by volume increases on renewal business and renewal pricing increases, primarily on property insurance and casualty coverages.

(10) Certain components of our gross premiums written include alternative market premiums. We currently cede either all or a portion of the alternative market premium, net of reinsurance, to three SPCs of our wholly owned Cayman Islands reinsurance subsidiary, Inova Re, which is reported in our Segregated Portfolio Cell Reinsurance segment (see further discussion in the Ceded Premiums Written section that follows). The portion not ceded to the SPCs is retained within our Specialty P&C segment.

Alternative market gross premiums written decreased in 2023 as compared to 2022 driven by the prior year impact of tail coverage, primarily related to one program in which we do not participate in the underwriting results.

We are committed to a rate structure that will allow us to fulfill our obligations to our insureds while generating competitive long-term returns for our shareholders. Our pricing continues to be based on expected losses as indicated by our historical loss data and available industry loss data. In recent years, this practice has resulted in rate increases and we anticipate further rate increases due to indications of increasing projected loss severity. Additionally, the pricing of our business includes the effects of filed rates, surcharges and discounts. Renewal pricing reflects changes in our exposure base, deductibles, self-insurance retention limits and other policy terms and conditions. See further explanation of changes in renewal pricing above under the heading "Gross Premiums Written".

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The change in renewal pricing for our Specialty P&C segment, including by major component, was as follows:

New business written by major component on a direct basis was as follows:

For our Specialty P&C segment, we calculate retention as annualized renewed premium divided by all annualized premium subject to renewal. Retention is affected by a number of factors. We may lose insureds to competitors or to alternative insurance mechanisms such as risk retention groups, captive arrangements or self-insurance entities (often when physicians join hospitals or large group practices) or due to pricing or other issues. We may choose not to renew an insured as a result of our underwriting evaluation. Insureds may also terminate coverage because they have left the practice of medicine for various reasons, principally for retirement, death or disability, but also for personal reasons. See further explanation of changes in retention above under the heading "Gross Premiums Written".

Retention for our Specialty P&C segment, including by major component, was as follows:

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Ceded Premiums Written

Ceded premiums represent the amounts owed to our reinsurers for their assumption of a portion of our losses. Our HCPL and Medical Technology Liability excess of loss reinsurance arrangements renew annually on October 1. For the October 1, 2023 renewal, both our HCPL and Medical Technology Liability treaties renewed at a higher rate than the previous treaties and we continue to generally retain the first $2 million in risk insured by us and cede coverages in excess of this amount. For our HCPL coverages in excess of $2 million, we generally retain from 9% to 9.5% of the next $24 million of risk which increased from a retention of 0% to 5% in the expiring treaty. For our Medical Technology Liability treaty, we do not retain any of the next $8 million of risk for coverages in excess of $2 million. All other material terms were consistent with the expiring treaties.

We pay our reinsurers a ceding premium in exchange for their accepting the risk, and in certain of our excess of loss arrangements, the ultimate amount of which is determined by the loss experience of the business ceded, subject to certain minimum and maximum amounts. Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As a result, we may have an adjustment to our estimate of expected losses and associated recoveries for prior year ceded losses under certain loss sensitive reinsurance agreements. Any changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

Ceded premiums written were as follows:

(1)We generally reinsure risks under our excess of loss reinsurance arrangements pursuant to which the reinsurers agree to assume all or a portion of all risks that we insure above our individual risk retention levels. Premium due to reinsurers is based on a rate factor applied to gross premiums written subject to cession under the arrangement. The increase in ceded premiums written under our excess of loss reinsurance arrangements in 2023 as compared to 2022 was driven by an increase in the overall volume of gross premiums written subject to cession and the impact of prior year adjustments on certain of our reinsurance arrangements reaching maximum limits eligible for cession on certain treaty years.

(2)We have entered into various shared risk arrangements, including quota share, fronting and captive arrangements, with certain large healthcare systems and other insurance entities. While we cede a large portion of the premium written under these arrangements, they provide us an opportunity to grow net premium through strategic partnerships. Ceded premiums written under these arrangements increased in 2023 as compared to 2022 driven by an increase in premium ceded under a particular arrangement with a hospital group and an existing insured entering into an arrangement during the first quarter of 2023.

(3)As previously discussed, as a part of our alternative market solutions, all or a portion of certain healthcare premium written is ceded to SPCs in our Segregated Portfolio Cell Reinsurance segment under either excess of loss or quota share reinsurance agreements, depending on the structure of the individual program. See the Segment Results - Segregated Portfolio Cell Reinsurance section for further discussion on the cession to the SPCs from our Specialty P&C segment. Premiums ceded to SPCs in 2023 decreased as compared to 2022 driven by the prior year impact of tail coverage, primarily related to one program in which we do not participate in the underwriting results.

(4)Given the length of time that it takes to resolve our claims, many years may elapse before all losses recoverable under a reinsurance arrangement are known. As a part of the process of estimating our loss reserve we also make estimates regarding the amounts recoverable under our reinsurance arrangements. As previously discussed, the premiums ultimately ceded under certain of our swing rated excess of loss reinsurance arrangements are subject to the losses ceded under the arrangements. As part of the review of our reserves for 2023 and 2022, we recorded a net decrease in our estimate of ceded premiums owed to reinsurers due to a decrease in our estimate of expected losses and associated recoveries for prior year ceded losses. Changes to estimates of premiums ceded related to prior accident years are fully earned in the period the changes in estimates occur.

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Ceded Premiums Ratio

As shown in the table below, our ceded premiums ratio was affected in both 2023 and 2022 by revisions to our estimate of premiums owed to reinsurers related to coverages provided in prior accident years. The ceded premiums ratio was as follows:

The above table reflects ceded premiums written, excluding the effect of prior year ceded premium adjustments, as previously discussed, as a percent of gross premiums written. Our current accident year ceded premiums ratio remained relatively unchanged for 2023 as compared to 2022.

Net Premiums Earned

Net premiums earned consist of gross premiums earned less the portion of earned premiums that we cede to our reinsurers for their assumption of a portion of our losses. Because premiums are generally earned pro rata over the entire policy period, fluctuations in premiums earned tend to lag those of premiums written. The majority of our policies carry a term of one year; however, some of our Medical Technology Liability policies have a multi-year term. Tail coverage premiums are generally 100% earned in the period written because the policies insure only incidents that occurred in prior periods and are not cancellable. Retroactive coverage premiums are 100% earned at the inception of the contract, as all of the associated underlying loss events occurred in the past. Additionally, any ceded premium changes due to changes to estimates of premiums owed under reinsurance agreements for prior accident years are fully earned in the period of change.

Net premiums earned were as follows:

Gross premiums earned decreased in 2023 as compared to 2022 driven by the pro rata effect of a decrease in the volume of written premium during the preceding twelve months due to competitive market conditions, our process of evaluating the NORCAL book of business and implementing ProAssurance's underwriting strategies and, to a lesser extent, our ceased participation in Syndicate 6131 for the 2022 underwriting year.

Ceded premiums earned during both 2023 and 2022 included prior accident year ceded premium adjustments under swing rated reinsurance agreements (see previous discussion in footnote 4 under the heading "Ceded Premiums Written"). After removing the effect of the prior accident year ceded premium adjustment from both years, ceded premiums earned increased by $2.1 million in 2023 as compared to 2022 driven by the pro rata effect of an increase in premium ceded under our excess of loss arrangements during the preceding twelve months.

Losses and Loss Adjustment Expenses

The determination of calendar year losses involves the actuarial evaluation of incurred losses for the current accident year and the actuarial re-evaluation of incurred losses for prior accident years.

Accident year refers to the accounting period in which the insured event becomes a liability of the insurer. For claims-made policies, which represent the majority of the premiums written in our Specialty P&C segment, the insured event generally becomes a liability when the event is first reported to us and the policy that is in effect at that time covers the claim. For occurrence policies, the insured event becomes a liability when the event takes place even though the claim may be reported to us at a later date. For retroactive coverages, the insured event becomes a liability at inception of the underlying contract. We believe that measuring losses on an accident year basis is the best measure of the underlying profitability of the premiums earned in that period, since it associates policy premiums earned with the estimate of the losses incurred related to those policy premiums.

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The following table summarizes calendar year net loss ratios for our Specialty P&C segment by separating losses between the current accident year and all prior accident years. The net loss ratios for our Specialty P&C segment were as follows:

(1)Net losses, as specified, divided by net premiums earned.

(2)For the year ended December 31, 2023, our current accident year net loss ratio (as shown in the table above), increased 0.9 percentage points as compared to 2022. The change in our current accident year net loss ratio was primarily attributable to the following:

•Excluding the impact of the items specifically identified in the table above, our current accident year net loss ratio remained relatively unchanged as compared to 2022. While we increased certain expected loss ratios in our HCPL line of business during the first quarter of 2023, this was more than offset by changes in the mix of business. We continue to observe higher than anticipated loss severity trends in select jurisdictions that started to emerge in the fourth quarter of 2022 and, as a result, we increased certain expected loss ratios in our HCPL line of business during the first quarter of 2023.

•As a result of our acquisition of NORCAL, our current accident year net loss ratio in 2022 was impacted by the purchase accounting amortization of $4.9 million related to the negative VOBA associated with NORCAL's assumed unearned premium which was recorded as a reduction to current accident year net losses. As of June 30, 2022, the negative VOBA was fully amortized which resulted in a 0.6 percentage point increase in the year ended December 31, 2023 ratio as compared to the prior year period.

We re-evaluate our previously established reserve each quarter based upon the most recently completed actuarial analysis supplemented by any new analysis, information or trends that have emerged since the date of that study. We also take into account currently available industry trend information.

The following table shows the components of our net prior accident year reserve development:

2023: The loss environment in our HCPL line of business continues to be challenging in some jurisdictions, as claim costs are pressured by social inflation and higher than anticipated loss severity trends which started to emerge in the fourth quarter of 2022. We are monitoring the impact that these trends have on our open case reserves and prior year development. Net unfavorable reserve development was driven by the strengthening of case reserves related to four large claims in our HCPL line of business (-$10.1 million) and unfavorable development associated with our Lloyd’s Syndicates operations (-$3.1 million), partially offset by net favorable development in other lines of business, predominately in our Medical Technology Liability line of business.

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The contingent consideration associated with the NORCAL acquisition is dependent upon the after-tax development of NORCAL’s 2020 and prior accident year reserves from December 31, 2020 to December 31, 2023. In the fourth quarter of 2023, we recognized unfavorable development in NORCAL’s 2020 and prior accident year reserves which was entirely offset by favorable development recognized in NORCAL’s 2021 and 2022 accident year reserves since acquisition. While these adjustments to NORCAL’s reserves had no impact to the segment’s net losses or net loss ratio, they contributed to the decrease in the fair value of the contingent consideration liability of $3.5 million in 2023 which was recorded as an offset to operating expenses in the segment. See further discussion that follows under the heading “Underwriting, Policy Acquisition and Operating Expenses.”

2022: Net favorable reserve development was driven by favorable development recognized in our Medical Technology Liability line of business (+$5.0 million), favorable development recognized in Small Business Unit line of business (+4.0 million), the remaining decrease to our previous IBNR reserve for COVID-19 (+$9.0 million) and net favorable development in our HCPL line of business (+$5.0 million), partially offset by unfavorable development associated with our Lloyd’s Syndicates operations (-$7.3 million) and increase to our reserve for potential ECO/XPL claims (-$4.0 million).

A detailed discussion of factors influencing our recognition of loss development is included in our Critical Accounting Estimates section under the heading "Reserve for Losses and Loss Adjustment Expenses." Assumptions used in establishing our reserve are regularly reviewed and updated by management as new data becomes available. Any adjustments necessary are reflected in the then current operations. Due to the size of our reserve, even a small percentage adjustment to the assumptions can have a material effect on our results of operations for the period in which the change is made, as was the case in both 2023 and 2022.

Underwriting, Policy Acquisition and Operating Expenses

Our Specialty P&C segment underwriting, policy acquisition and operating expenses were comprised as follows:

DPAC amortization increased in 2023 as compared to 2022 primarily due to an increase in compensation-related expenses due to an increase in headcount and, to a lesser extent, an increase in agency commissions. In addition, DPAC amortization for 2022 reflected the impact of purchase accounting from the NORCAL acquisition which resulted in DPAC amortization being approximately $1.0 million lower than would have otherwise been recognized for the period due to the application of GAAP purchase accounting rules. Under these purchase accounting rules, the capitalized policy acquisition costs for NORCAL policies written prior to the acquisition date were written off through purchase accounting on May 5, 2021 rather than being expensed pro rata over the remaining term of the associated policies.

Management fees are charged pursuant to a management agreement by the Corporate segment to the core domestic operating subsidiaries within our Specialty P&C segment for services provided based on the extent to which services are provided to the subsidiary and the amount of premium written by the subsidiary. While the terms of the management agreement were generally consistent between 2023 and 2022, fluctuations in the amount of premium written by each subsidiary can result in corresponding variations in the management fee charged to each subsidiary during a particular period.

Other underwriting and operating expenses decreased in 2023 as compared to 2022 primarily attributable to the following:

•Certain one-time expenses of $3.9 million incurred during 2022 and a decrease in amounts accrued for performance-related incentive plans in 2023 due to the decline of the related performance metrics. One-time expenses during 2022 were mainly comprised of one-time bonuses, accelerated depreciation associated with a decommissioned IT system, employee severance charges and lease exit costs.

•A claim for a payroll tax refund of $3.8 million recognized in 2023 as a reduction to operating expenses related to the employee retention credit available to us under the CARES Act. See additional discussion on the ERC in Note 1 of the Notes to Consolidated Financial Statements and previous discussion in the Liquidity section under the heading "Taxes."

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•A reduction to operating expenses of $3.5 million in 2023 related to the remeasurement of the contingent consideration liability associated with the NORCAL acquisition due to unfavorable development recognized on NORCAL's 2020 and prior accident year reserves during the year. See additional discussion on the contingent consideration in the previous section under the heading "Losses and Loss Adjustment Expenses" and in the Critical Accounting Estimates section under the heading "Contingent Consideration."

•The decrease in other underwriting and operating expenses was partially offset by an increase in compensation-related expenses in 2023 due to organizational structure changes and the movement of certain employees from the Corporate segment to the Specialty P&C segment beginning in the third quarter of 2022.

Underwriting Expense Ratio (the Expense Ratio)

Our expense ratio for the Specialty P&C segment was as follows:

The change in our expense ratio in 2023 as compared to 2022 was primarily attributable to the following:

Excluding the impact of the items specifically identified in the table above, our expense ratio increased in 2023 by 1.4 percentage points as compared to 2022 primarily driven by higher compensation-related expenses due to the aforementioned organizational structure changes in 2022 and, to a lesser extent, an increase in travel-related expenses, partially offset by a decrease in amounts accrued for performance-related incentive plans.

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Segment Results - Workers' Compensation Insurance

Our Workers' Compensation Insurance segment includes workers' compensation products provided to employers generally with 1,000 or fewer employees, as discussed in Note 16 of the Notes to Consolidated Financial Statements. Workers' compensation products offered include guaranteed cost policies, policyholder dividend policies, retrospectively-rated policies, deductible policies and alternative market programs. Alternative market programs include services related to program design, fronting, claims administration, risk management, SPC rental, asset management and SPC management services. Alternative market program premiums are 100% ceded to either the SPCs within our Segregated Portfolio Cell Reinsurance segment or captive insurers unaffiliated with ProAssurance for two programs. Our Workers' Compensation Insurance segment results reflect pre-tax underwriting profit or loss from these workers' compensation products, exclusive of investment results, which are included in our Corporate segment. Segment results included the following:

Premiums Written

Our workers’ compensation premium volume is driven by five primary factors: (1) the amount of new business written, (2) retention of our existing book of business, (3) premium rates charged on our renewal book of business, (4) changes in payroll exposure and (5) audit premium.

Gross, ceded and net premiums written were as follows:

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Gross Premiums Written

Gross premiums written by product were as follows: