Unum Group (UNM) FY 2023 MD&A

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

The discussion and analysis presented in this section should be read in conjunction with the "Cautionary Statement Regarding Forward-Looking Statements" included below the Table of Contents, "Risk Factors" included herein Item 1A, and the Consolidated Financial Statements and notes thereto included in Item 8.

Prior financial information has been adjusted to reflect our modified retrospective adoption, effective January 1, 2023, of the Accounting Standards Update (ASU) 2018-12, related to targeted improvements to the accounting for long-duration contracts. Changes from this ASU were applied as of January 1, 2021, also referred to as the transition date. See Note 1 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

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Executive Summary

2023 Operating Performance and Capital Management

For 2023, we reported net income of $1,283.8 million, or $6.50 per diluted common share, compared to net income of $1,407.2 million, or $6.96 per diluted common share, in 2022.

Included in our results for 2023 are:

•A net investment loss of $36.0 million before tax and $28.2 million after tax, or $0.14 per diluted common share;

•Amortization of the cost of reinsurance of $44.1 million before tax and $34.8 million after tax, or $0.18 per diluted common share;

•Non-contemporaneous reinsurance of $34.8 million before tax and $27.5 million after tax or $0.14 per diluted common share; and

•A net reserve increase related to assumption updates of $177.2 million before tax and $139.3 million after tax, or $0.70 per diluted common share.

Included in our results for 2022 are:

•A net investment loss of $15.7 million before tax and $12.2 million after tax, or $0.07 per diluted common share;

•Amortization of the cost of reinsurance of $50.3 million before tax and $39.7 million after tax, or $0.20 per diluted common share;

•Non-contemporaneous reinsurance of $34.4 million before tax and $27.2 million after tax or $0.13 per diluted common share; and

•A net reserve decrease related to assumption updates of $243.3 million before tax and $192.1 million after tax, or $0.96 per diluted common share.

Excluding these items, after-tax adjusted operating income for 2023 was $1,513.6 million, or $7.66 per diluted common share compared to $1,294.2 million, or $6.40 per diluted common share for 2022. See "Reconciliation of Non-GAAP and Other Financial Measures" contained herein in this Item 7 for a reconciliation of these items.

Our Unum US segment reported income before income tax and net investment gains and losses of $1,484.3 million in 2023 compared to $1,143.4 million in 2022, which include the reserve assumption updates that occurred during the third quarters of 2023 and 2022. Excluding these items, our Unum US segment reported adjusted operating income of $1,355.5 million in 2023 compared to $972.6 million in 2022, due to favorable benefits experience primarily in our group product lines and an increase in premium income, partially offset by higher operating expenses and lower net investment income. The benefit ratio, excluding the reserve assumption updates, for our Unum US segment for 2023 was 59.8 percent, compared to 66.3 percent in 2022. Unum US sales increased 15.1 percent in 2023 compared to 2022.

Our Unum International segment reported income before income tax and net investment gains and losses of $140.2 million in 2023 compared to $141.6 million in 2022, which include the reserve assumption updates during the third quarters of 2023 and 2022. Excluding these items, our Unum International segment reported adjusted operating income, as measured in U.S. dollars, of $158.1 million in 2023 compared to $134.0 million in 2022. As measured in local currency, our Unum UK line of business reported adjusted operating income, which excludes the reserve assumption updates, of £124.6 million in 2023 compared to £109.0 million in 2022 due to favorable benefits experience in the group long-term disability product line and higher premium income, partially offset by lower net investment income and higher operating expenses. The benefit ratio for our Unum UK line of business, excluding the reserve assumption updates, was 69.0 percent in 2023 compared to 79.3 percent in 2022. Unum International sales, as measured in U.S. dollars, increased 27.8 percent in 2023 compared to 2022. Unum UK sales, as measured in local currency, increased 18.6 percent in 2023 compared to 2022.

Our Colonial Life segment reported income before income tax and net investment gains and losses of $480.8 million in 2023 compared to $468.1 million in 2022, which include the reserve assumption updates during the third quarters of 2023 and 2022. Excluding these items, our Colonial Life segment reported adjusted operating income of $400.1 million in 2023 compared to $412.9 million in 2022, primarily due to higher amortization of deferred acquisition costs and operating expenses, partially offset by higher premium income and favorable benefit experience. The benefit ratio, excluding the reserve assumption updates, for Colonial Life was 50.9 percent in 2023 compared to 51.8 percent in 2022. Colonial Life sales increased 6.2 percent in 2023 compared to 2022.

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Our Closed Block segment reported a loss before income tax and net investment gains and losses of $282.8 million in 2023 compared to income before income tax and net investment gains and losses of $176.9 million in 2022, which include the amortization of the cost of reinsurance and the impact of non-contemporaneous reinsurance related to the Closed Block individual disability reinsurance transaction, as well as the reserve assumption updates. Excluding these items, our Closed Block segment reported adjusted operating income of $164.9 million in 2023 compared to $251.9 million in 2022. The net premium ratio for long-term care increased to 93.5 percent at December 31, 2023 from 85.1 percent at December 31, 2022. The interest adjusted loss ratio for long-term care, excluding reserve assumption updates, was unfavorable during 2023 compared to 2022.

A rising interest rate environment could positively impact our yields on new investments, but could also create unrealized losses in our current holdings. Alternatively, a declining interest rate environment could negatively impact our yields on new investments, but could also reduce unrealized losses in our current holdings. As of December 31, 2023, we do not hold any securities with a decline in fair value below amortized cost which we intend to sell nor any securities for which it is more likely than not that we will be required to sell before recovery in amortized cost. The net unrealized loss on our fixed maturity securities was $1.6 billion and $3.0 billion at December 31, 2023 and 2022, respectively, with the decrease due primarily to a decrease in corporate bond spreads and to a lesser extent the portfolio repositioning that we executed in the third quarter of 2023. The earned book yield on our investment portfolio decreased to 4.45 percent for 2023 compared to a yield of 4.57 percent for 2022.

Additionally, a rising interest rate environment could result in reserve decreases while a declining interest rate environment could result in reserve increases, specific to our liability for future policy benefits, as the reserve discount rate assumptions used in the calculation of our liability are updated at each reporting date using a yield that is reflective of an upper-medium grade fixed income instrument, which is generally equivalent to a single-A interest rate matched to the duration of certain of our insurance liabilities. The change in discount rate assumptions on the liability for future policy benefits, net of reinsurance, due primarily to the decrease in credit spreads during 2023, resulted in an increase to the liability for future policy benefits, net of reinsurance, of approximately $1.2 billion.

We believe our capital and financial positions are strong. At December 31, 2023, the RBC ratio for our traditional U.S. insurance subsidiaries, calculated on a weighted average basis using the NAIC Company Action Level formula, was approximately 415 percent, which is in line with our expectations. We repurchased 5.7 million shares of Unum Group common stock under our share repurchase program, at a cost of approximately $252 million, including commissions and excise tax, during 2023. In December 2023, we retired 115.0 million shares of our treasury stock with a total cost of $3,642.5 million. Our weighted average common shares outstanding, assuming dilution, equaled 197.6 million and 202.1 million for 2023 and 2022, respectively. As of December 31, 2023, Unum Group and our intermediate holding companies had available holding company liquidity of $1,650 million that was held primarily in bank deposits, commercial paper, money market funds, corporate bonds, municipal bonds, and asset backed securities.

2023, 2022, and 2021 Reserve Assumption Updates

During the third quarters of 2023, 2022, and 2021, we completed our annual cash flow assumption review and updated certain of our assumptions used to develop the liability for future policy benefits. For more information see "Critical Accounting Estimates" included herein in this Item 7 as well as Note 6 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Inflation Reduction Act

In August 2022, the Inflation Reduction Act (IRA) was signed into law in the U.S. and includes certain corporate tax provisions effective January 1, 2023. The IRA imposes a new 15 percent corporate alternative minimum tax (CAMT) on adjusted financial statement income (AFSI) on corporations that have average AFSI over $1.0 billion in any prior three-year period, starting with years 2020 to 2022. Our company is an applicable corporation. We have not recorded any CAMT as of December 31, 2023. We do not expect that any CAMT incurred would impact earnings since it would be offset with a credit toward regular income tax in subsequent years. The IRA also imposes a one percent excise tax on fair market value of corporate stock repurchases after December 31, 2022. This excise tax is recorded as part of the cost basis of treasury stock and is assessed on the fair market value of stock purchases, reduced by the fair value of any shares issued during the period. We have recorded $1.9 million of excise tax in stockholders' equity, as part of the cost basis of treasury stock in 2023.

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Impairment Loss on Internal-Use Software

During the third quarter of 2021, we recognized an impairment loss of $12.1 million before tax, or $9.6 million after tax, for previously capitalized internal-use software that we no longer plan to utilize. We determined that this internal-use software would no longer be developed in order to focus our efforts on the development of software that better supports our long-term strategic goals. For further information related to the impairment loss on internal-use software, see Note 15 of the "Notes to Consolidated Financial Statements" contained in Item 8.

Impairment Losses on Right-of-Use (ROU) Asset

During the second quarter of 2021, we recognized an impairment loss of $13.9 million before tax, or $11.0 million after tax, on the ROU asset related to one of our operating leases for office space that we do not plan to continue using to support our general operations. The impairment loss was recorded as a result of a decrease in the fair value of the ROU asset compared to its carrying value. For further information related to the impairment loss on the ROU asset, see Note 17 of the "Notes to Consolidated Financial Statements" contained in Item 8.

U.K. Tax Law Change

In June 2021, the Finance Act 2021 was enacted, resulting in a U.K. tax rate increase from 19 percent to 25 percent, effective April 1, 2023, which resulted in $23.6 million of additional tax expense in operating earnings for the revaluation of our deferred tax assets and liabilities in 2021.

Closed Block Individual Disability Reinsurance Transaction

In December 2020, we completed the first phase of a reinsurance transaction, pursuant to which Provident Life and Accident Insurance Company, The Paul Revere Life Insurance Company, and Unum Life Insurance Company of America, wholly-owned domestic insurance subsidiaries of Unum Group, and collectively referred to as "the ceding companies", each entered into separate reinsurance agreements with Commonwealth Annuity and Life Insurance Company (Commonwealth), to reinsure on a coinsurance basis effective as of July 1, 2020, approximately 75 percent of the Closed Block individual disability business, primarily direct business written by the ceding companies. On March 31, 2021, we completed the second phase of the reinsurance transaction, pursuant to which the ceding companies and Commonwealth amended and restated their respective reinsurance agreements to reinsure on a coinsurance and modified coinsurance basis effective as of January 1, 2021, a substantial portion of the remaining Closed Block individual disability business that was not ceded in December 2020, primarily business previously assumed by the ceding companies.

In December 2020, Provident Life and Casualty Insurance Company (PLC), also a wholly-owned domestic insurance subsidiary of Unum Group, entered into an agreement with Commonwealth whereby PLC will provide a 12-year volatility cover to Commonwealth for the active life cohort (ALR cohort). On March 31, 2021, PLC and Commonwealth amended and restated this agreement to incorporate the ALR cohort related to the additional business that was reinsured between the ceding companies and Commonwealth as part of the second phase of the transaction. As part of the amended and restated volatility cover, PLC received a payment from Commonwealth of approximately $18 million.

In connection with the second phase of the reinsurance transaction, Commonwealth paid a total ceding commission to the ceding companies of $18.2 million. The ceding companies transferred assets of $767.0 million, which consisted primarily of cash and fixed maturity securities. In addition, we recognized the following in 2021 related to the second phase:

•Net realized investment gains totaling $67.6 million, or $53.4 million after tax, related to the transfer of investments.

•Transaction costs totaling $6.2 million, or $5.0 million after tax.

•Reinsurance recoverable of $1,132.5 million related to the policies on claim status (DLR cohort).

•A reduction to the cost of reinsurance, or prepaid reinsurance premium, of $99.4 million related to the DLR cohort.

•Deposit asset of $5.0 million related to the ALR cohort.

•Payable of $307.2 million related to the portfolio of invested assets associated with the business ceded on a modified coinsurance basis.

We amortized the cost of reinsurance related to both Phase 1 and Phase 2 of $44.1 million or $34.8 million after tax in 2023, $50.3 million or $39.7 million after tax in 2022, and $69.8 million or $55.1 million after tax in 2021.

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We released approximately $200 million of capital during the first quarter of 2021. See "Reinsurance" contained herein in Item 1, "Segment Results" contained herein in Item 7, and Note 14 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion on the impacts related to this reinsurance transaction.

Consolidated Company Outlook for 2024

We believe our strategy of providing financial protection products at the workplace puts us in a position of strength. We continue to fulfill our corporate purpose of helping the working world thrive throughout life’s moments by providing excellent service to people at their time of need. Our strategy remains centered on growing our core businesses, through investing and transforming our operations and technology to anticipate and respond to the changing needs of our customers, expanding into new adjacent markets through meaningful partnerships and effective deployment of our capital across our portfolio.

In 2023, we experienced increased earnings driven by the underlying strength of our business and expect positive operating trends in our core businesses to continue in 2024. The products and services we provide deliver significant value to employers, employees and their families, and we believe this will help drive sales and premium growth in 2024.

A rising interest rate environment could continue to positively impact yields on new investments, but could also continue to create unrealized losses in our current holdings. A declining interest rate environment could negatively impact our yields on new investments but could also reduce unrealized losses in our current holdings. We also may continue to experience further volatility in miscellaneous investment income primarily related to changes in partnership net asset values as well as bond calls.

As part of our discipline in pricing and reserving, we continuously monitor emerging claim trends and interest rates. We will continue to take appropriate pricing actions on new business and renewals that are reflective of the current environment and may continue to utilize derivative financial instruments to manage interest rate risk.

Our business is well-diversified by geography within our markets, industry exposures and case size, and we continue to analyze and employ strategies that we believe will help us navigate the current environment. These strategies allow us to maintain financial flexibility to support the needs of our businesses, while also returning capital to our shareholders. We have strong core businesses that have a track record of generating significant free cash flow, and we will continue to invest in our operations and expand into adjacent markets where we can best leverage our expertise and capabilities to capture market growth opportunities as those opportunities emerge. We believe that consistent operating results, combined with the implementation of strategic initiatives and the effective deployment of capital, will allow us to meet our financial objectives.

Further discussion is included in "Reconciliation of Non-GAAP and Other Financial Measures," "Consolidated Operating Results," "Segment Results," "Investments," and "Liquidity and Capital Resources" contained herein in this Item 7 and in the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Reconciliation of Non-GAAP and Other Financial Measures

We analyze our performance using non-GAAP financial measures. A non-GAAP financial measure is a numerical measure of a company's performance, financial position, or cash flows that excludes or includes amounts that are not normally excluded or included in the most directly comparable measure calculated and presented in accordance with U.S generally accepted accounting principles (GAAP). The non-GAAP financial measure of "after-tax adjusted operating income" differs from net income as presented in our consolidated operating results and income statements prepared in accordance with GAAP due to the exclusion of investment gains or losses, the amortization of the cost of reinsurance, the impact of non-contemporaneous reinsurance, and reserve assumption updates as well as certain other items as specified in the reconciliations below. Investment gains or losses primarily include realized investment gains or losses, expected investment credit losses, and gains or losses on derivatives. We believe after-tax adjusted operating income is a better performance measure and better indicator of the profitability and underlying trends in our business.

Investment gains or losses depend on market conditions and do not necessarily relate to decisions regarding the underlying business of our segments. Our investment focus is on investment income to support our insurance liabilities as opposed to the generation of investment gains or losses. Although we may experience investment gains or losses which will affect future earnings levels, a long-term focus is necessary to maintain profitability over the life of the business since our underlying business is long-term in nature, and we need to earn the interest rates assumed in calculating our liabilities.

Cash flow assumptions used to calculate our liability for future policy benefits are reviewed at least annually and updated, as needed, with the resulting impact reflected in net income. While the effects of these assumption updates are recorded in the

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reporting period in which the review is completed, these updates reflect experience emergence and changes to expectations spanning multiple periods. We believe that by excluding the impact of reserve assumption updates we are providing a more comparable and consistent view of our quarterly results.

We exited a substantial portion of our Closed Block individual disability product line through the two phases of the reinsurance transaction that were executed in December 2020 and March 2021. As a result, we exclude the amortization of the cost of reinsurance that we recognized upon the exit of the business related to the policies on claim status as well as the impact of non-contemporaneous reinsurance that resulted from the adoption of ASU 2018-12. Due to the execution of the second phase of the reinsurance transaction occurring after January 1, 2021, the transition date of ASU 2018-12, in accordance with the provisions of the ASU related to non-contemporaneous reinsurance, we were required to establish the ceded reserves using an upper-medium grade fixed-income instrument as of the reinsurance transaction date in March 2021 which resulted in higher ceded reserves compared to that which was reported historically. However, the direct reserves for the block reinsured in the second phase were calculated using the original discount rate utilized as of the transition date. Both the direct and ceded reserves are then remeasured at each reporting period using a current discount rate reflective of an upper-medium grade fixed-income instrument, with the changes recognized in OCI. While the total equity impact is neutral, the different original discount rates utilized for direct and ceded reserves result in disproportionate earnings impacts. The impact of non-contemporaneous reinsurance will fluctuate depending on the magnitude of reserve changes during the period. We believe that the exclusion of these items provides a better view of our results from our ongoing businesses.

We may at other times exclude certain other items from our discussion of financial ratios and metrics in order to enhance the understanding and comparability of our operational performance and the underlying fundamentals, but this exclusion is not an indication that similar items may not recur and does not replace net income or net loss as a measure of our overall profitability.

See "Executive Summary" contained herein in Item 7 and Notes 3, 6, 9, 10, 14, 15, and 17 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion regarding the items specified in the reconciliations below.

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A reconciliation of GAAP financial measures to our non-GAAP financial measures is as follows:

We measure and analyze our segment performance on the basis of "adjusted operating revenue" and "adjusted operating income" or "adjusted operating loss," which differ from total revenue and income before income tax as presented in our consolidated statements of income due to the exclusion of investment gains and losses, the amortization of the cost of reinsurance, the impact of non-contemporaneous reinsurance, reserve assumption updates, as well as certain other items as specified in the reconciliations below. These performance measures are in accordance with GAAP guidance for segment reporting, but they should not be viewed as a substitute for total revenue, income before income tax, net income, or net loss.

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A reconciliation of total revenue to "adjusted operating revenue" and income before income tax to "adjusted operating income" is as follows:

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Critical Accounting Estimates

We prepare our financial statements in accordance with GAAP. The preparation of financial statements in conformity with GAAP requires us to make estimates and assumptions that affect amounts reported in our financial statements and accompanying notes. Estimates and assumptions could change in the future as more information becomes known, which could impact the amounts reported and disclosed in our financial statements.

The accounting estimates deemed to be most critical to our financial position and results of operations are those related to the liability for future policy benefits, valuation of investments, pension and postretirement benefit plans, income taxes, and contingent liabilities. For additional information, refer to our significant accounting policies in Note 1 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Liability for Future Policy Benefits

Liabilities for future policy benefits represent the cost of claims that we estimate we will eventually pay to our policyholders and the related expenses for our non interest-sensitive products. Liability for future policy benefits includes policy liabilities for claims not yet incurred and for claims that have been incurred or are estimated to have been incurred but not yet reported to us. Liability for future policy benefits equaled $40.0 billion and $38.6 billion at December 31, 2023 and 2022, or approximately 74.6 percent and 73.6 percent of our total liabilities, respectively. Liability for future policy benefits ceded to reinsurers was $7.8 billion and $8.1 billion at December 31, 2023 and 2022, respectively, and are reported as a reinsurance recoverable in our consolidated balance sheets.

Liabilities for future policy benefits are initially established in the same period in which we issue a policy, and equal the difference between projected future policy benefits and projected future premiums, allowing a margin for expenses and profit. The liabilities for future policy benefits build up and release over time, based on the emergence of cash flows, including premiums received and claims paid, and updated expectations for future cash flows.

Liabilities for future policy benefits are updated at each reporting date to reflect changes in the liability based on policy development over time, emerging experience, and any assumption updates required to maintain the best estimate basis for expected future cash flows as required by GAAP. These future policy benefit liabilities are based on actual known facts regarding the liability, such as the benefits available under the applicable policy, the covered benefit period, the age, and, as appropriate, the occupation and cause of disability of the claimant, as well as assumptions derived from our actual historical experience and expected future changes in experience for factors such as the claim duration, claim administration expenses, discount rate, policy benefit offsets, including those for social security and other government-based welfare benefits. The liability for future policy benefits also includes the liabilities for incurred claims.

Future policy benefit liabilities primarily relate to our traditional long-duration products which include our group, individual disability and certain of our voluntary benefits products in our Unum US segment; group, individual disability and life products in our Unum International segment; certain of our voluntary benefits products in our Colonial Life segment; and long-term care and certain of our other products in our Closed Block segment.

In calculating the liability for future policy benefits, our long-duration contracts are grouped into cohorts by product type and contract issue year. Liabilities for future policy benefits for claims not yet incurred are generally determined using the net premium model as prescribed by GAAP. At each reporting period, the liability for future policy benefits is remeasured at the current discount rate with the change recorded in other comprehensive income.

The calculation of the liability for future policy benefits involves numerous assumptions including discount rate, lapses, mortality, and morbidity. Certain product lines may utilize additional assumptions in calculating the liability for future policy benefits in addition to those listed above such as premium rate increases for long-term care, benefit offsets for Unum US long-term disability, claim costs for Unum US voluntary benefits and Colonial Life, and inflation-linked benefits for Unum UK group disability and group life. Claim costs capture the combined effect of the incidence rate, the expected level of benefit to be paid, and the claim resolution rate. Cash flow assumptions are reviewed and updated, as needed, at least annually. Assumptions may be updated more frequently, if necessary, based on trending experience.

On a quarterly basis, cohort level cash flow measures are updated based on the emergence of actual experience. The updated cash flows, based on experience emergence and any assumption updates, are used to determine the updated net premiums, the portion of the gross premium required to provide for all benefits and expenses, excluding acquisition costs or any costs that are required to be charged to expense as incurred. The updated net premium ratio is used to calculate the updated liability for

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future policy benefits as of the beginning of year, at the original discount rate. To the extent the present value of future benefits and expenses exceeds the present value of future gross premiums, an immediate charge is recognized in net income, such that net premiums are set equal to gross premiums. Future policy benefit liabilities are floored at zero at the cohort level in situations where the liabilities for future policy benefits are less than zero. The change in the liability for future policy benefits, at the original discount rate, as of the beginning of the period, resulting from cash flow changes is reflected as the change in benefits - remeasurement gain or loss in the consolidated statements of income. The impact of all other changes in the liability for future policy benefits are reflected as policy benefits in the consolidated statements of income.

Key Assumptions

The calculation of the liability for future policy benefits involves numerous assumptions, but the primary assumptions used to calculate the liability are (1) the discount rate, (2) the claim resolution rate, (3) the claim incidence rate, and (4) policyholder lapse and mortality:

1.The discount rate, which is used in calculating the liability for future policy benefits, is the interest rate that we use to discount future cash flows including premium and claim payments to determine the present value. A higher discount rate produces a lower reserve. If the discount rate is higher than our future investment returns, our invested assets will not earn enough investment income to support our future claim payments. The original discount rates are initially set at the transition date of ASU 2018-12, which was January 1, 2021, for policies originally issued on or before the transition date, or at the policy issuance date, for policies issued after the transition date. For policies issued after the transition date, the original discount rate assumptions reflect an upper-medium grade (low-credit risk) fixed-income instrument yield based on the currency in which the liabilities are assumed. For all cohorts, the liability is then remeasured at each reporting period using the current discount rate reflective of an upper-medium grade fixed-income instrument. We primarily utilize a forward curve which is derived from the underlying spot curve using interpolation to develop an ultimate forward rate.

2.The claim resolution rate is the probability that a disability or long-term care claim will close due to recovery or death of the insured and it is used to estimate how long benefits will be paid for a claim. Estimated resolution rates that are set too high will result in liabilities that are lower than they need to be to pay the claim benefits over time. Claim resolution assumptions involve many factors, including the cause of disability, the policyholder's age, the type of contractual benefits provided, and the time since initial disability. We primarily use our own claim experience to develop our claim resolution assumptions. These assumptions are established for the probability of death and the probability of recovery from disability. Our studies incorporate actual claim resolution experience over a number of years and consider any observed trends over the study period. We also consider any expected future changes in claim resolution experience.

3.The incidence rate is the rate at which new claims are submitted to us. The incidence rate is affected by many factors, including the age of the insured, the insured's occupation or industry, the benefit plan design, and certain external factors such as consumer confidence and levels of unemployment. We establish our incidence assumption using a historical review of actual incidence results along with an outlook of future incidence expectations.

4.Policyholder lapse and mortality assumptions reflect the probability that insureds’ coverage is discontinued due to lapsation or death of the insured. For our life insurance products, mortality assumptions also reflect the probability that a benefit payment occurs. These rates are affected by many factors, including the age of the insured, the insured's occupation or industry, the benefit plan design, and the length of time from policy or certificate issue to valuation date. We establish our mortality and lapse assumptions using a historical review of actual results along with an outlook of future expectations.

Establishing liability for future policy benefit assumptions is complex and involves many factors. Liabilities for future policy benefits, particularly for policies offering insurance coverage for long-term disabilities and long-term care, are dependent on numerous assumptions other than just those presented in the preceding discussion. The impact of internal and external events, such as changes in claims operational procedures, economic trends such as the rate of unemployment and the level of consumer confidence, the emergence of new diseases, new trends and developments in medical treatments, and legal trends and legislative changes, including changes to social security and other government-based welfare benefits programs which provide policy benefit offsets, among other factors, will influence claim incidence rates, claim resolution rates, and claim costs. In addition, for policies offering coverage for disability or long-term care at advanced ages, the level and pattern of mortality rates at advanced ages will impact overall benefit costs. Reserve assumptions differ by product line and by policy type within a product line. Additionally, in any period and over time, our actual experience may have a positive or negative variance from our long-

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term assumptions, either singularly or collectively, and these variances may offset each other. We review our assumptions at least annually with a long-term view of our expected experience over the life of a block of business rather than test just one or a few assumptions independently that may be aberrant over a short period of time. Based on this review, we update our assumptions to reflect our current best estimates. Therefore, while it is possible to evaluate the sensitivity of overall results in our liability for future policy benefits based upon a change in each individual assumption, the actual impacts of changes to a variety of underlying assumptions must be considered in the aggregate by product line in order to judge the overall potential implications to the liability for future policy benefits. The following sections present the impacts of our most recent cash flow assumption reviews and an overview of our trend analysis for key assumptions and the results of variability in our assumptions, in aggregate, for the liabilities for future policy benefits which we believe are reasonably possible to have a material impact on our future financial results if actual claims yield a materially different amount than what we currently expect and have reserved for, either favorable or unfavorable.

Cash Flow Assumption Review

Our cash flow assumption reviews during the years ended December 31, 2023, 2022, and 2021 resulted in the following impacts to income before income tax as a result of updating certain assumptions related to the liability for future policy benefits:

2023 Significant Cash Flow Assumption Updates:

The cash flow assumption updates in our Unum US group long-term disability product line reduced our liability for future policy benefits by $121.0 million, due primarily to sustained improvement in claim recovery trends since our last assumption update.

The cash flow assumption updates in our Colonial Life segment reduced our liability for future policy benefits by $80.7 million, due primarily to improvement in certain of our claim cost assumptions and increased policyholder lapse rates since our last assumption update.

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The cash flow assumption updates in our Closed Block segment were primarily driven by the long-term care product line which increased our liability for future policy benefits by $368.1 million, due primarily to lower expectations for active policy lapse and mortality assumptions, partially offset by an increase to expected future premium rate increases.

2022 Significant Cash Flow Assumption Updates:

The cash flow assumption updates in our Unum US group long-term disability product line and our waiver of premium benefits for our Unum US group life product line reduced our liability for future policy benefits by $121.0 million and $34.0 million, respectively, due primarily to sustained improvement in claim recovery trends since our last assumption update, partially offset by lower social security benefit offsets for our group long-term disability product line.

The cash flow assumption updates in our Colonial Life segment reduced our liability for future policy benefits by $55.2 million, due primarily to improvement in certain of our claim cost assumptions since our most recent assumption update.

The cash flow assumption updates in our Closed Block segment were primarily driven by the all other product line. The impact to income before income tax for this product line was $6.8 million and related to the small block of retained individual disability business. However, there were also updates to the mortality assumptions for the advanced age portion of our individual disability claimant population which was included in the block ceded as a part of the Closed Block individual disability reinsurance transaction with Commonwealth Annuity and Life Insurance Company. We increased our liability for future policy benefits by $196.0 million as a result of the assumption updates related to the ceded advanced age claimant block with a corresponding increase in our consolidated balance sheet as a reinsurance recoverable.

2021 Significant Cash Flow Assumption Updates:

The cash flow assumption updates in our Unum US group long-term disability product line reduced our liability for future policy benefits by $215.0 million, due primarily to sustained improvement in claim recovery trends since our last assumption update.

Trends in Key Assumptions

Generally, we do not expect our mortality and morbidity claim incidence trends or our persistency trends to change significantly in the short-term, and to the extent that these trends do change, we expect those changes to be gradual over a longer period of time. We have historically experienced an increase in our group long-term disability morbidity claim incidence trends during and following a recessionary period and believe claim incidence trends may continue to somewhat follow general economic conditions and demographics of the general workforce.

The long-term discount rates underlying our liabilities are reflective of rates based on the issue year of the cohort or rates underlying the liabilities at transition to the updated accounting basis as prescribed by ASU 2018-12. The discount rate assumption for new cohorts, after the transition date, is based on the interest rate of an upper-medium grade fixed-income instrument for that cohort period.

Our claim resolution rate assumption used in determining the liability for future policy benefits is our expectation of the resolution rate we will experience over the life of the block of business and will vary from actual experience in any one period, both favorably and unfavorably. Claim resolution rates are very sensitive to operational and environmental changes and have a greater chance of significant variability in a shorter period of time than our other reserve assumptions. These rates are reviewed on a quarterly basis for the death and recovery components separately. While claim resolution rates in our Unum US group long-term disability product line have shown some variability over the last several years, they have exhibited an increasing trend.

Sensitivity Analysis

We monitor our key assumptions and test the sensitivity of our liability for future policy benefits under a range of scenarios. This sensitivity analysis is completed at least annually and was last completed as of December 31, 2023 for our product lines with a higher level of estimation uncertainty and utilizes the liability for future policy benefits valued at the original discount rate. See "Quantitative and Qualitative Disclosures about Market Risk" contained herein in Item 3 for information regarding the sensitivity of the current discount rate used to remeasure the liability for future policy benefits at each reporting date.

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In our estimation, scenarios based on certain variations in each of our assumptions for our Unum US group long-term disability product line could produce a change of approximately $100 million which represents 1.9 percent of our Unum US group disability liability for future policy benefits balance. Of the assumptions impacting the estimated change in the liability for future policy benefits, the largest contributor is the claim resolution rate for which we assumed a change of approximately 10 percent.

In our estimation, scenarios based on certain possible variations in each of our assumptions for our Colonial Life segment could produce a change of approximately $60 million which represents 3.0 percent of our Colonial Life liability for future policy benefits balance. Of the assumptions impacting the estimated change in the liability for future policy benefits, the largest contributor is the claim costs, for which we assumed a change of approximately 10 percent.

We also consider variability in our assumptions related to the long-term care liability for future policy benefits. In our estimation, scenarios based on certain variations in each of our assumptions could produce potential results as illustrated in the chart below. The liability for future policy benefits for long-term care is based upon a number of key assumptions, and each assumption has various factors which may impact the long-term outcome. Key assumptions with respect to active policy lapses and mortality, claim incidence and resolutions, and future premium rate increases must incorporate extended views of expectations for many years into the future. The liability for future policy benefits is highly sensitive to these estimates. Key assumptions and related impacts are also heavily interrelated in both their outcome and in their effects on the liability for future policy benefits. For example, changes in the view of morbidity and mortality might be mitigated by either potential future premium rate increases and/or morbidity improvements due to general improvement in health and/or medical breakthroughs. There is a potentially wide range of outcomes for each assumption and in totality. As a result, and given the size of the long-term care liability for future policy benefits in relation to the total liability for future policy benefits, our sensitivity analysis for long-term care reflects the potential impact to the present value of gross liability cash flows for future policy benefits for updates to our key assumptions. The sensitivity analysis related to our key assumptions for the long-term care liability for future policy benefits is as shown below. The impact of changes to these assumptions would partially be reflected in the period in which the assumptions are updated and partially across future periods. Given the significant changes in certain assumptions, the below sensitivity analysis was completed as of the beginning of the third quarter of 2023 at which point the most recent assumption update review occurred.

The impact to current period liability for future benefits would be smaller in magnitude than the present value of gross liability for future policy benefits cash flows due to the updating of the net premium ratio. The current period liability for future policy benefits impact may be asymmetrical (i.e. larger for the unfavorable scenario) for some sensitivities if the assumption update causes the net premium ratio to be capped at 100 percent for any given cohort.

We believe that these sensitivities provide a reasonable estimate of the possible changes in liability for future policy benefit balances for those product lines where we believe it is possible that variability in the assumptions, in the aggregate, could result in a material impact on our liability for future policy benefit levels, but we record our liability for future policy benefits based on our long-term best estimate for our cohorts and these assumptions are reviewed and updated annually to reflect the current best estimates. Product lines that have long-term claim payout periods have a greater potential for significant variability in claim costs, either positive or negative. We closely monitor emerging experience and use these results to inform our view of long-term assumptions.

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Fair Value of Investments

All of our fixed maturity securities, which are classified as available-for-sale, and all of our unrestricted equity securities are reported at fair value. Our derivative financial instruments, including certain derivative instruments embedded in other contracts, are reported as either assets or liabilities and measured at fair value. We report our investments in private equity partnerships at our share of the partnerships' net asset value or its equivalent (NAV), as a practical expedient for fair value.

Fair value is 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 and therefore represents an exit price, not an entry price. The exit price objective applies regardless of our intent and/or ability to sell the asset or transfer the liability at the measurement date. We generally use valuation techniques consistent with the market approach, and to a lesser extent, the income approach. The market approach uses prices and other relevant information from market transactions involving identical or comparable assets or liabilities and the income approach converts future amounts, such as cash flows or earnings, to a single present value amount, or a discounted amount. We believe the market approach valuation technique provides more observable data than the income approach, considering the types of investments we hold.

The degree of judgment utilized in measuring the fair value of financial instruments generally correlates to the level of pricing observability. Financial instruments with readily available active quoted prices or for which fair value can be measured from actively quoted prices in active markets generally have more pricing observability and less judgment utilized in measuring fair value. The market sources from which we obtain or derive the fair values of our assets and liabilities carried at market value include quoted market prices for actual trades, price quotes from third party pricing vendors, price quotes we obtain from outside brokers, discounted cash flow, and observable prices for similar publicly traded or privately traded issues that incorporate the credit quality and industry sector of the issuer. Our fair value measurements could differ significantly based on the valuation technique and available inputs.

Inputs to valuation techniques refer broadly to the assumptions that market participants use in pricing assets or liabilities, including assumptions about risk, for example, the risk inherent in a particular valuation technique used to measure fair value and/or the risk inherent in the inputs to the valuation technique. We use observable and unobservable inputs in measuring the fair value of our financial instruments. Observable inputs are inputs that reflect the assumptions market participants would use in pricing the asset or liability developed based on market data obtained from independent sources. Unobservable inputs are developed based on the best information available in the circumstances, and reflect our evaluation of the assumptions market participants would use in pricing the asset or liability.

Certain of our investments do not have readily determinable market prices and/or observable inputs or may at times be affected by the lack of market liquidity. For these securities, we use internally prepared valuations, including valuations based on estimates of future profitability, to estimate the fair value. Additionally, we may obtain prices from independent third-party brokers to aid in establishing valuations for certain of these securities. Key assumptions used by us to determine fair value for these securities include risk-free interest rates, risk premiums, performance of underlying collateral (if any), and other factors involving significant assumptions which may or may not reflect those of an active market.

As of December 31, 2023, approximately 11.6 percent of our fixed maturity securities were categorized as Level 1, 88 percent as Level 2, and 0.4 percent as Level 3. Level 1 is the highest category of the three-level fair value hierarchy classification wherein inputs are unadjusted and represent quoted prices in active markets for identical assets or liabilities. The Level 2 category includes assets or liabilities valued using inputs (other than those included in the Level 1 category) that are either directly or indirectly observable for the asset or liability through correlation with market data at the measurement date and for the duration of the instrument's anticipated life. The Level 3 category is the lowest category of the fair value hierarchy and reflects the judgment of management regarding what market participants would use in pricing assets or liabilities at the measurement date using unobservable inputs to extrapolate an estimated fair value.

Rapidly changing credit and equity market conditions can materially impact the valuation of securities, and the period to period changes in value can vary significantly.

See "Quantitative and Qualitative Disclosures about Market Risk" for information regarding the sensitivity of the estimated fair value for fixed maturity securities contained herein in Item 7A. See Note 2 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

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Investment Credit Losses

One of the significant estimates related to investments is our credit loss valuation. In determining when a decline in fair value below amortized cost of a fixed maturity security represents a credit loss, we evaluate the following factors:

•Whether we expect to recover the entire amortized cost basis of the security

•Whether we intend to sell the security or will be required to sell the security before the recovery of its amortized cost basis

•Whether the security is current as to principal and interest payments

•The significance of the decline in value

•Current and future business prospects and trends of earnings

•The valuation of the security’s underlying collateral

•Relevant industry conditions and trends relative to their historical cycles

•Market conditions

•Rating agency and governmental actions

•Bid and offering prices and the level of trading activity

•Adverse changes in estimated cash flows for securitized investments

•Changes in fair value subsequent to the balance sheet date

•Any other key measures for the related security

We evaluate available information, including the factors noted above, both positive and negative, in reaching our conclusions. In particular, we also consider the strength of the issuer’s balance sheet, its debt obligations and near term funding requirements, cash flow and liquidity, the profitability of its core businesses, the availability of marketable assets which could be sold to increase liquidity, its industry fundamentals and regulatory environment, and its access to capital markets. Although all available and applicable factors are considered in our analysis, our expectation of recovering the entire amortized cost basis of the security, whether we intend to sell the security, whether it is more likely than not we will be required to sell the security before recovery of its amortized cost, and whether the security is current on principal and interest payments are the most critical factors in determining whether a credit loss is possible. The significance of the decline in value is also an important factor, but we generally do not record a credit loss based solely on this factor, since often other more relevant factors will impact our evaluation of a security.

While determining whether a credit loss exists is a judgmental area, we utilize a formal, well-defined, and disciplined process to monitor and evaluate our fixed income investment portfolio, supported by issuer specific research and documentation as of the end of each period. The process results in a thorough evaluation of investments and the recording of credit losses on a timely basis for investments determined to have credit loss.

We use a comprehensive rating system to evaluate the investment and credit risk of our mortgage loans and to identify specific properties for inspection and reevaluation. We estimate an allowance for credit losses that we expect to incur over the life of our mortgage loans using a probability of default method. For each loan, we estimate the probability that the loan will default before its maturity (probability of default) and the amount of the loss if the loan defaults (loss given default). These two factors result in an expected loss percentage that is applied to the amortized cost of each loan to determine the expected credit loss. Mortgage loans are reported at amortized cost less the allowance for expected credit losses with the change in expected credit losses recognized as an investment gain or loss in our consolidated statements of income.

There are a number of significant risks inherent in the process of monitoring our investments for credit losses and determining when and if a credit loss exists. These risks and uncertainties include the following possibilities:

•The assessment of a borrower's ability to meet its contractual obligations will change.

•The economic outlook, either domestic or foreign, may be less favorable or may have a more significant impact on the borrower than anticipated, and as such, the investment may not recover in value.

•New information may become available concerning the security, such as disclosure of accounting irregularities, fraud, or corporate governance issues.

•Significant changes in credit spreads may occur in the related industry.

•Significant increases in interest rates may occur and may not return to levels similar to when securities were initially purchased.

•Adverse rating agency actions may occur.

See Notes 1 and 3 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

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Pension and Postretirement Benefit Plans

We sponsor several defined benefit pension and other postretirement benefit (OPEB) plans for our employees, including non-qualified pension plans. The U.S. qualified and non-qualified defined benefit pension plans comprise the majority of our total benefit obligation and benefit cost. We maintain a separate defined benefit plan for eligible employees in our U.K. operation. The U.S. defined benefit pension plans were closed to new entrants on December 31, 2013, the OPEB plan was closed to new entrants on December 31, 2012, and the U.K. plan was closed to new entrants on December 31, 2002.

Assumptions

Our net periodic benefit costs and the value of our benefit obligations for these plans are determined based on a set of economic and demographic assumptions that represent our best estimate of future expected experience. Major assumptions used in accounting for these plans include the expected discount (interest) rate, the long-term rate of return on plan assets, and mortality rates. We also use, as applicable, expected increases in compensation levels and a weighted average annual rate of increase in the per capita cost of covered benefits, which reflects a health care cost trend rate, and the U.K. plan also uses expected cost of living increases to plan benefits.

The assumptions chosen for our pension and OPEB plans are reviewed annually, using a December 31 measurement date for each of our plans unless we are required to perform an interim remeasurement. The discount rate, expected long-term rate of return, and mortality rate assumptions have the most significant effect on our net periodic benefit costs associated with these plans. In addition to the effect of changes in our assumptions, the net periodic cost or benefit obligation under our pension and OPEB plans may change due to factors such as plan amendments, actual experience being different from our assumptions, special benefits to terminated employees, and/or changes in benefits provided under the plans.

•Discount rate - This interest assumption is based on the yield derived from a portfolio of high quality fixed income corporate debt instruments that reasonably match the timing and amounts of projected future benefits for each of our retirement-related benefit plans. The rate is determined at the measurement date.

•Long-term rate of return - This assumption is selected from a range of probable return outcomes from an analysis of the asset portfolio. The market-related value as it relates to our estimate of long-term rate of return equals the fair value of plan assets, determined as of the measurement date. The return on plan assets recognizes all asset gains and losses, including changes in fair value, through the measurement date. Our expectations for the future investment returns of the asset categories are based on a combination of historical market performance, evaluations of investment forecasts obtained from external consultants and economists, and current market yields. The expected return for the total portfolio is calculated based on the plan's strategic asset allocation. The actual rate of return on plan assets is determined based on the fair value of the plan assets at the beginning and the end of the period, adjusted for contributions and benefit payments. A lower long-term rate of return on plan assets increases our net periodic benefit cost.

Investment risk is measured and monitored on an ongoing basis through annual liability measurements, periodic asset/liability studies, and quarterly investment portfolio reviews.  Risk tolerance is established through consideration of plan liabilities, plan funded status, and corporate financial condition. We believe our investment portfolios are well diversified by asset class and sector, with no undue risk concentrations in any one category. See Note 11 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion of the investment portfolios for our plans.

•Mortality rate - This assumption reflects our best estimate, as of the measurement date, of the life expectancies of plan participants in order to determine the expected length of time for benefit payments. We derive our assumptions from industry mortality tables.

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The weighted average assumptions used in the measurement of our net periodic benefit costs for the years ended December 31 are as follows:

The following illustrates the sensitivity of the below items to a 50 basis point change in the discount rate or the expected long-term rate of return on plan assets:

Benefit Obligation and Fair Value of Plan Assets

During 2023, the fair value of plan assets in our U.S. qualified defined benefit pension plan decreased from $1,308.3 million to $1,295.9 million, or 0.9 percent, due to benefits and expenses paid, mostly offset by a favorable return on assets which resulted in a gain of approximately 11.1 percent. During 2023, the fair value of plan assets in our U.K. plan decreased from £116.3 million to £114.2 million, or 1.8 percent, due primarily to the payment of benefits, mostly offset by a favorable return on assets which resulted in a gain of approximately 2.1 percent. Although our rate of return on plan assets for 2023 differed from our assumptions used in the measurement of our net periodic benefit costs, we believe our assumptions appropriately reflect the impact of the current economic environment and our expectations for the future investment returns based on the plan's asset allocation.

As of December 31, 2023, our pension and OPEB plans have an aggregate unrecognized net actuarial loss of $584.0 million and an unrecognized prior service credit of $1.5 million, which together represent the cumulative liability and asset gains and losses as well as the portion of prior service credits that have not been recognized in pension expense. The unrecognized net actuarial loss for our pension plans, which is $605.2 million at December 31, 2023, will be amortized over the average remaining life expectancy of the plan, which is approximately 24 years for the U.S. plans and 27 years for the U.K. plan, to the extent that it exceeds the 10 percent corridor, as described below. The unrecognized net actuarial gain of $21.2 million for our OPEB plan will be amortized over the average remaining life expectancy of the plan, estimated at twelve years, to the extent the gain is outside of the corridor. The corridor for the pension and OPEB plans is established based on the greater of 10 percent of the plan assets or 10 percent of the benefit obligation.  At December 31, 2023, $352.7 million of the actuarial loss was outside of the corridor for the U.S. plans and £61.1 million was outside of the corridor for the U.K. plan. At December 31, 2023, $13.3 million of the actuarial gain was outside of the corridor for the OPEB plan.

The amortization of the unrecognized actuarial gain or loss and the unrecognized prior service credit is a component of our net periodic benefit cost and equaled $7.0 million, $15.5 million, and $22.4 million in 2023, 2022, and 2021, respectively.

The U.S. qualified defined benefit pension plan was in an underfunded position of $116.2 million and $118.7 million at December 31, 2023 and December 31, 2022, respectively. This year-over-year change was due primarily to a favorable return on plan assets, mostly offset by the increase in the benefit obligation due to the decrease in discount rate.

The U.K. plan was in an underfunded position of £21.2 million and £14.4 million at December 31, 2023 and 2022, respectively. This year-over-year change was primarily driven by the increase in the benefit obligation due to the decrease in discount rate and unfavorable plan experience, partially offset by a favorable return on plan assets.

The fair value of plan assets in our OPEB plan was $8.2 million and $8.5 million at December 31, 2023 and 2022, respectively. These assets represent life insurance contracts to fund the life insurance benefit portion of our OPEB plan. Our OPEB plan

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represents a non-vested, non-guaranteed obligation, and current regulations do not require specific funding levels for these benefits, which are comprised of retiree life, medical, and dental benefits. It is our practice to use general assets to pay medical and dental claims as they come due in lieu of utilizing plan assets for the medical and dental benefit portions of our OPEB plan.

See Note 11 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion.

Income Taxes

We provide for federal, state, and foreign income taxes currently payable, as well as those deferred due to temporary differences between the financial reporting and tax bases of assets and liabilities.  Our accounting for income taxes represents our best estimate of various events and transactions. The calculation of our tax liabilities involves dealing with uncertainties in the application of complex tax laws in a multitude of jurisdictions, both domestic and foreign.  The amount of income taxes we pay is subject to ongoing audits in various jurisdictions, and a material assessment by a governing tax authority could affect profitability.

We record a valuation allowance to reduce deferred tax assets to the amount that is more likely than not to be realized.  Significant judgment is required in determining valuation allowances. In evaluating the ability to recover deferred tax assets, we consider all available positive and negative evidence including past operating results, the existence of cumulative losses in the most recent years, forecasted earnings, future taxable income, and prudent and feasible tax planning strategies.  We consider our investment strategies when evaluating the ability to recover deferred tax assets on unrealized losses on investments. In the event we determine that we more likely than not will not be able to realize all or part of our deferred tax assets in the future, an increase to the valuation allowance is recorded in the period such determination is made.  Likewise, if it is later determined that it is more likely than not that those deferred tax assets will be realized, the previously provided valuation allowance is reversed.

In establishing a liability for unrecognized tax benefits, assumptions are made in determining whether, and to what extent, a tax position may be sustained. GAAP prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in income tax returns. The evaluation of a tax position is a two step process. The first step is to determine whether it is more likely than not that a tax position will be sustained upon examination based on the technical merits of the position. The second step is to measure a position that satisfies the recognition threshold at the largest amount of benefit that is greater than 50 percent likely of being realized upon ultimate settlement. Tax positions that previously failed to meet the more likely than not threshold but that now satisfy the recognition threshold are recognized in the first subsequent financial reporting period in which that threshold is met. Previously recognized tax positions that no longer meet the more likely than not recognition threshold are derecognized in the first subsequent financial reporting period in which that threshold is no longer met. If a previously recognized tax position is settled for an amount that is different from the amount initially measured, the difference will be recognized as a tax benefit or expense in the period the settlement is effective.

Changes in tax laws, tax regulations, or interpretations of such laws or regulations, could have an impact on our provision for income tax and our effective tax rate, which could significantly affect the amounts reported in our financial statements.

See "Regulation" contained herein in Item 1. See Note 9 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Contingent Liabilities

On a quarterly basis, we review relevant information with respect to litigation and contingencies to be reflected in our consolidated financial statements. An estimated loss is accrued when it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. It is possible that our results of operations or cash flows in a particular period could be materially affected by an ultimate unfavorable outcome of pending litigation or regulatory matters depending, in part, on our results of operations or cash flows for the particular period.  See Note 16 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

Accounting Developments

For information on new accounting standards and the impact, if any, on our financial position or results of operations, see Note 1 of the "Notes to Consolidated Financial Statements" contained herein in Item 8.

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Consolidated Operating Results

Fluctuations in exchange rates, particularly between the British pound sterling and the U.S. dollar for our U.K. operations, have an effect on our consolidated financial results. In periods when the pound weakens relative to the preceding period, translating pounds into dollars decreases current period results relative to the prior period. In periods when the pound strengthens, translating pounds into dollars increases current period results relative to the prior period.

The weighted average pound/dollar exchange rate for our Unum UK line of business was 1.243, 1.221, and 1.378 for 2023, 2022, and 2021, respectively. If the 2022 and 2021 results for our U.K. operations had been translated at the 2023 weighted average exchange rate, our adjusted operating revenue would have been approximately $5 million higher and $73 million lower in 2022 and 2021, respectively. Additionally, our adjusted operating income would have been approximately $2 million higher and $10 million lower in 2022 and 2021, respectively. However, it is important to distinguish between translating and converting foreign currency. Except for a limited number of transactions, we do not actually convert pounds into dollars. As a result, we view foreign currency translation as a financial reporting item and not a reflection of operations or profitability in the U.K.

We reported year-over-year premium growth in 2023 and 2022 in each of our principal operating business segments, primarily due to in-force block growth and higher overall sales. Premium income continues to decline, as expected, in our Closed Block segment.

Net investment income was lower in 2023, relative to 2022, due to lower miscellaneous investment income, primarily related to smaller increases in the NAV on our private equity partnerships, and lower investment income from inflation index-linked bonds held by Unum UK, partially offset by a higher level of invested assets and an increased yield on invested assets. Net investment income was lower in 2022, relative to 2021, due to lower miscellaneous investment income and a decline in the

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yield on invested assets, partially offset by higher investment income from inflation index-linked bonds held by Unum UK and a higher level of invested assets.

Credit losses on fixed maturity securities of $2.2 million were recognized in net investment gains and losses in 2023 compared to $4.6 million and $9.3 million in 2022 and 2021, respectively. During the third quarter of 2023, we sold over $700 million of shorter duration bonds in our long-term care portfolio and reinvested the proceeds in higher quality, higher yielding, and longer duration bonds that better match our liability cash flows. We realized approximately $35 million of investment losses as a result of these sales. Also included in net investment gains and losses were changes in the fair value of an embedded derivative in a modified coinsurance arrangement, which resulted in gains of $12.4 million, $16.2 million, and $9.7 million in 2023, 2022, and 2021, respectively. The changes in the embedded derivative are primarily driven by movements in credit spreads in the overall investment market. Included in the net investment gains and losses in 2021 was a net realized investment gain of $67.6 million related to the transfer of investments in the Closed Block individual disability reinsurance transaction. See Notes 3 and 4 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion.

Other income is primarily comprised of fee-based service products in the Unum US segment, which include leave management services and administrative services only business, and the underlying results and associated net investment income of certain assumed blocks of reinsured business in the Closed Block segment.

Overall benefits experience was favorable in 2023 relative to 2022 and 2021 with a consolidated benefit ratio of 72.2 percent in 2023, compared to 72.7 percent and 79.7 percent in 2022 and 2021, respectively. Excluding the impacts of the reserve assumption updates and non-contemporaneous reinsurance, the consolidated benefit ratios were 70.1 percent, 74.9 percent, and 81.9 percent in 2023, 2022, and 2021, respectively. For further discussion on the reserve assumption updates and non-contemporaneous reinsurance, see the "Executive Summary" contained herein in this Item 7 and Notes 1, 6 and 15 of the "Notes to Consolidated Financial Statements" contained herein in Item 8. The underlying benefits experience for each of our operating business segments is discussed more fully in "Segment Results" contained herein in this Item 7.

Commissions and the deferral of acquisition costs were higher in 2023 compared to 2022 driven primarily by higher overall sales and in-force block growth in our principal operating segments. The increase in the amortization of deferred acquisition costs in 2023 compared to 2022 is due primarily to increased growth in the level of the deferred asset and the impact of policyholder lapses in our Colonial Life segment and in our Unum US supplemental and voluntary product lines. Commissions and the deferral of acquisition costs were higher in 2022 compared to 2021 driven primarily by higher sales in our Colonial Life segment and Unum US supplemental and voluntary product line. Also contributing to the year-over-year growth in commissions during 2022 was in-force block growth and favorable persistency in our Unum US group disability product line. The amortization of deferred acquisition costs was lower in 2022 compared to 2021 due primarily to a decrease in the average amortization period in our Unum US group disability and group life and accidental death and dismemberment product lines that occurred in 2021, partially offset by higher policyholder lapses in our Colonial Life accident, sickness, and disability product line.

In 2022, cost related to early retirement of debt includes costs associated with the redemption of $350.0 million aggregate principal amount of our 4.000% senior notes due 2024 and costs related to the retirement of $14.0 million aggregate liquidation amount of the 7.405% capital securities due 2038 issued by Provident Financing Trust I (the Trust), which resulted in the reduction of a corresponding principal amount of our 7.405% junior subordinated debt securities due 2038 then held by the Trust. In 2021, cost related to early retirement of debt includes costs associated with the purchase and retirement of $500.0 million aggregate principal amount of our 4.500% senior notes due 2025. See Note 10 of the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further information.

We reported year-over-year increases in other expenses and compensation expense, on a combined basis, in both 2023 and 2022 due primarily to increases in employee-related costs, operational investments in our business, and growth in our fee-based service products, partially offset by a reduction in the amortization of the cost of reinsurance.

Our effective income tax rate for 2023 was 21.7 percent, compared to 19.6 percent in 2022 and 22.2 percent in 2021. Our 2023 effective tax rate was generally consistent with the U.S. statutory rate. Our 2022 effective tax rate differed from the U.S. statutory rate due to the foreign tax rate differential. Our 2021 effective tax rate differed from the U.S. statutory rate due to unfavorable impacts of the U.K. tax rate increase enacted in 2021. See Note 9 in the "Notes to Consolidated Financial Statements" contained herein in Item 8 for further discussion.

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Consolidated Sales Results

Shown below are sales results for our three principal operating business segments.

Sales shown in the preceding chart generally represent the annualized premium income on new sales which we expect to receive and report as premium income during the next 12 months following or beginning in the initial quarter in which the sale is reported, depending on the effective date of the new sale. Sales do not correspond to premium income reported as revenue in accordance with GAAP. This is because new annualized sales premiums reflect current sales performance and what we expect to recognize as premium income over a 12 month period, while premium income reported in our financial statements is reported on an "as earned" basis rather than an annualized basis and also includes renewals and persistency of in-force policies written in prior years as well as current new sales.

Sales, persistency of the existing block of business, employment and salary growth, and the effectiveness of a renewal program are indicators of growth in premium income. Trends in new sales, as well as existing market share, also indicate the potential for growth in our respective markets and the level of market acceptance of price levels and new product offerings. Sales results may fluctuate significantly due to case size and timing of sales submissions.

See "Segment Results" as follows for a discussion of sales by segment.

Segment Results

Our reporting segments are comprised of the following: Unum US, Unum International, Colonial Life, Closed Block, and Corporate. Financial information for each of our reporting segments is as follows.

In describing our results, we may at times note certain items and exclude the impact on financial ratios and metrics to enhance the understanding and comparability of our operational performance and the underlying fundamentals, but this exclusion is not an indication that similar items may not recur. We also measure and analyze our segment performance on the basis of "adjusted operating revenue" and "adjusted operating income" or "adjusted operating loss", which differ from total revenue and income before income tax as presented in our consolidated statements of income due to the exclusion of investment gains and losses and certain other items. These performance measures are in accordance with GAAP guidance for segment reporting, but they should not be viewed as a substitute for total revenue, income before income tax, or net income.  See "Reconciliation of Non-GAAP Financial Measures" contained herein in this Item 7.

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Unum US Segment

The Unum US segment is comprised of the group disability, group life and accidental death and dismemberment, and supplemental and voluntary lines of business. The group disability line of business includes long-term and short-term disability, medical stop-loss, and fee-based service products. The supplemental and voluntary line of business includes voluntary benefits, individual disability, and dental and vision products.

Unum US Operating Results

Shown below are financial results for the Unum US segment. In the sections following, financial results and key ratios are also presented for the major lines of business within the segment.

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Unum US Group Disability Operating Results

Shown below are financial results and key performance indicators for Unum US group disability.

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Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

Premium income was higher compared to 2022, driven primarily by in-force block growth and higher sales. Net investment income was lower compared to 2022 primarily due to a lower level of invested assets. Other income increased relative to 2022 due to growth in our fee-based service products.

The benefit ratio, excluding the impacts of the reserve assumption updates, was favorable compared to 2022 due primarily to lower claim incidence, favorable recoveries, and favorable discount rate impacts on new claims in our group long-term disability product line. New claims for our group products are established using the discount rate based on an upper-medium grade fixed-income instrument, which is generally equivalent to a single-A interest rate, as of the policy issuance or policy renewal date. As a result, the higher discount rates on new claims compared to 2022 contributed to the favorable benefits experience during 2023.

Commissions and the deferral of acquisition costs were higher compared to 2022 due primarily to in-force block growth and higher sales. The amortization of deferred acquisition costs was higher compared to 2022 due to growth in the level of the deferred asset. The other expense ratio, which includes other income that is primarily related to fee-based service products, was consistent compared to 2022.

Year Ended December 31, 2022 Compared with Year Ended December 31, 2021

Premium income increased compared to 2021, driven primarily by in-force block growth and favorable persistency. Net investment income was lower compared to 2021 due to lower miscellaneous investment income, a decrease in the yield on invested assets, and a lower level of invested assets. Other income increased relative to 2021 due primarily to continued growth in our fee-based service products.

The benefit ratio, excluding the impacts of the reserve assumption updates, was favorable compared to 2021 due primarily to lower claims incidence in both the group short-term and long-term disability product lines as well as favorable claim recoveries in our group long-term disability product line.

Commissions were higher compared to 2021 due primarily to in-force block growth and favorable persistency. The deferral of acquisition costs was higher compared to 2021 due primarily to higher sales. The amortization of deferred acquisition costs was lower compared to 2021 due primarily to a decrease in the average amortization period that occurred in 2021. The other expense ratio increased compared to 2021 due primarily to increases in employee-related costs and an increase in operational investments in our business, particularly related to our growing fee-based service business.

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Unum US Group Life and Accidental Death and Dismemberment Operating Results

Shown below are financial results and key performance indicators for Unum US group life and accidental death and dismemberment.

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Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

Premium income was higher compared to 2022 due primarily to higher sales and favorable persistency. Net investment income was lower compared to 2022 due to a decrease in the level of invested assets and lower miscellaneous investment income, partially offset by an increase in the yield on invested assets.

The benefit ratio, excluding the impact of the reserve assumption update in 2022, was favorable compared to 2022 due primarily to lower mortality, resulting primarily from lessening impacts of COVID-19 on our insured population.

Commissions were higher compared to 2022 due primarily to higher sales. The deferral of acquisition costs and the amortization of deferred acquisition costs were generally consistent compared to 2022. The other expense ratio was generally consistent compared to 2022.

Year Ended December 31, 2022 Compared with Year Ended December 31, 2021

Premium income was higher compared to 2021 driven by in-force block growth, partially offset by lower persistency. Net investment income was lower compared to 2021 due to lower miscellaneous investment income, partially offset by an increase in the level of invested assets and an increase in the yield on invested assets.

The benefit ratio, excluding the impact of the reserve assumption update, was favorable compared to 2021 largely due to lower mortality in the group life product line, resulting primarily from lessening impacts of COVID-19 on our insured population.

Commissions were higher compared to 2021 due primarily to in-force block growth. The deferral of acquisition costs was generally consistent compared to 2021. The amortization of deferred acquisition costs was lower compared to 2021 due primarily to a decrease in the average amortization period that occurred in 2021. The other expense ratio increased compared to 2021 due primarily to an increase in employee-related costs and operational investments in our business.

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Unum US Supplemental and Voluntary Operating Results

Shown below are financial results and key performance indicators for Unum US supplemental and voluntary product lines.

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Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

Premium income was higher compared to 2022 due primarily to higher sales across all product lines as well as the partial recapture of a previously ceded block of business in the individual disability product line, partially offset by a lower persistency across all product lines. Net investment income was generally consistent compared to 2022 with a decline in the yield on invested assets and lower miscellaneous investment income, mostly offset by an increase in the level of invested assets. Other income was higher compared to 2022 due primarily to a net gain on the partial recapture of a previously ceded block of business in the individual disability product line.

The benefit ratio for voluntary benefits, excluding the impacts of the reserve assumption updates, was favorable compared to 2022 due primarily to the impact of policyholder lapses in the disability product line and lower mortality in the life product line. The benefit ratio for the individual disability product line, excluding the impacts of the reserve assumption updates, was favorable compared to 2022 due primarily to higher mortality and lower claims incidence. The benefit ratio for the dental and vision product line was unfavorable compared to 2022 due primarily to higher claims incidence.

Commissions and the deferral of acquisition costs were higher compared to 2022 due primarily to higher sales in the individual disability and voluntary benefits product lines. The amortization of deferred acquisition costs was higher compared to 2022 due to growth in the level of the deferred asset and the impact of the policyholder lapses in the voluntary benefits product line. The other expense ratio increased compared to 2022 due primarily to an increase in employee-related costs and an increase in operational investments in our business.

Year Ended December 31, 2022 Compared with Year Ended December 31, 2021

Premium income was generally consistent with 2021, with a decline in the voluntary benefits product line, mostly offset by growth in the individual disability and dental and vision product lines. Net investment income decreased compared to 2021 due primarily to lower miscellaneous investment income and a decrease in the level of invested assets.

The benefit ratio for voluntary benefits, excluding the impacts of the reserve assumption updates, was favorable compared to 2021 due to favorable experience in most products, including within the life product line resulting primarily from lessening impacts of COVID-19 on our insured population. The benefit ratio for the individual disability product line, excluding the impacts of the reserve assumption updates, was unfavorable compared to 2021 due primarily to a change in estimate related to the unearned premium reserve in the fourth quarter of 2022 as well as higher average benefit size. The benefit ratio for the dental and vision product line was favorable compared to 2021 due primarily to lower claims incidence.

Commissions and the deferral of acquisition costs were higher compared to 2021 due primarily to higher sales in the individual disability and voluntary benefits product lines. The amortization of deferred acquisition costs was generally consistent compared to 2021. The other expense ratio increased compared to 2021 due primarily to an increase in employee-related costs, a net loss recognized in the fourth quarter of 2022 on the recapture of a block of business in the voluntary benefits product line, and an increase in operational investments in our business, partially offset by a decrease in the allowance for expected credit losses on premium receivable balances.

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Sales

Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

Group sales increased compared to 2022 primarily due to higher sales to new customers in both the large case market and the core market, which we define as employee groups with fewer than 2,000 employees. The sales mix in the group market sector for 2023 was approximately 63 percent core market and 37 percent large case market.

Voluntary benefits sales increased compared to 2022 due to higher sales to new and existing customers in both the large case and core markets. Individual disability sales, which are primarily concentrated in the multi-life market, increased compared to 2022 due to higher sales to both new and existing customers. Dental and vision sales increased compared to 2022 driven by higher sales to new customers.

Year Ended December 31, 2022 Compared with Year Ended December 31, 2021

Group sales increased compared to 2021 due to higher sales to new and existing customers in both the large case market and the core market. The sales mix in the group market sector for 2022 was approximately 63 percent core market and 37 percent large case market.

Voluntary benefits sales increased compared to 2021 primarily due to higher sales to existing customers in the core market and higher sales to new customers in the large case market. Individual disability sales increased compared to 2021 due to higher sales to both new and existing customers. Dental and vision sales increased compared to 2021 driven by higher sales to both new and existing customers.

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Goodwill

We had total goodwill of $280.0 million for the Unum US segment at December 31, 2023, none of which is currently believed to be at risk for future impairment.

Segment Outlook

We remain committed to offering consumers a broad set of financial protection benefit products at the worksite. During 2024, we will continue to invest in a unique customer experience defined by simplicity, empathy, and deep industry expertise through the increased utilization of digital capabilities and technology to enhance enrollment, underwriting, the client administration experience, and claims processing. In addition, we will focus on strategically driven sales by enhancing the connectivity, alignment, and support for brokers and technology partners. With respect to smaller employers, we will continue to provide a comprehensive set of consumer-focused products, enhance our distribution model, and utilize our digital tools to bring industry leading enrollment capabilities and a fully integrated customer experience. Our differentiated offerings and market leading leave management services provide substantial growth opportunities, particularly with larger employers, and stronger persistency in our core products. We believe our active client management, integrated customer experience across our product lines, and strong risk management, will enable us to continue to grow our market over the long-term.

We expect strong adjusted operating income in 2024 with continued premium growth and claim experience in line with 2023. We expect premium growth to be driven by improved persistency in most lines as well as continued strong sales momentum. We expect the group disability market to remain competitive which may impact our pricing and renewal premium levels. We expect favorable group disability claim experience to continue in 2024, driven by strong operational performance. We also expect group life and voluntary benefits claim experience to be mostly stable. We expect a stable operating expense ratio as our investments in our people and capabilities are offset by efficiencies gained from our strategic initiatives.

A rising interest rate environment could continue to positively impact our yields on new investments but could also continue to create further unrealized losses in our current holdings. A declining interest rate environment could negatively impact yields on new investments but could also reduce unrealized losses in our current holdings. Our net investment income may continue to be impacted by volatility in miscellaneous investment income.

As part of our discipline in pricing and reserving, we continuously monitor emerging claim trends and interest rates. We will continue to take appropriate pricing actions on new business and renewals that are reflective of the current environment.

We continuously monitor key indicators to assess our risks and adjust our business plans accordingly.

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Unum International Segment

The Unum International segment is comprised of our operations in both the United Kingdom and Poland. Our Unum UK products include insurance for group long-term disability, group life, and supplemental lines of business, which includes dental, individual disability, and critical illness products. Our Unum Poland products include insurance for individual and group life with accident and health riders. Unum International's products are sold primarily through field sales personnel and independent brokers and consultants.

Operating Results

Shown below are financial results and key performance indicators for the Unum International segment.

Foreign Currency Translation

The functional currencies of Unum UK and Unum Poland are the British pound sterling and Polish zloty, respectively. Premium income, net investment income, claims, and expenses are received or paid in the functional currency, and we hold functional currency-denominated assets to support functional currency-denominated policy liabilities. We translate functional currency-denominated financial statement items into dollars for our consolidated financial reporting. We translate income statement items using an average exchange rate for the reporting period, and we translate balance sheet items using the exchange rate at the end of the period. We report unrealized foreign currency translation gains and losses in accumulated other comprehensive income (loss) in our consolidated balance sheets.

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Fluctuations in exchange rates impact Unum International's reported financial results and our consolidated financial results. In periods when the functional currency strengthens relative to the preceding period, translation increases current period results relative to the prior period. In periods when the functional currency weakens, translation decreases current period results relative to the prior period.

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Unum UK Operating Results

Shown below are financial results and key performance indicators for the Unum UK product lines in functional currency.

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Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

Premium income was higher compared to 2022 primarily due to in-force block growth and sales growth in the group life and supplemental product lines.

Net investment income was lower compared to 2022 due to lower investment income from inflation index-linked bonds. Our investments in inflation index-linked bonds support the claim liabilities associated with certain group policies that provide for inflation-linked increases in policy benefits. The change in net investment income attributable to these index-linked bonds is partially offset by a change in policy benefits related to the inflation index-linked group long-term disability and group life policies.

The benefit ratio, excluding the reserve assumption updates, was favorable relative to 2022 due to favorable claim incidence, favorable claim resolutions, higher discount rates on new claims in the group long-term disability product line, and lower inflation-linked experience in benefits. This favorability was partially offset by higher incidence in the supplemental product line and higher mortality in the group life product line.

Commissions increased relative to 2022 due primarily to in-force block growth and higher sales. The deferral of acquisition costs and the amortization of deferred acquisition costs were generally consistent relative to 2022. The other expense ratio was higher relative to 2022 due to an increase in employee-related costs and operational investments in the business.

Year Ended December 31, 2022 Compared with Year Ended December 31, 2021

Premium income was higher compared to 2021 primarily due to in-force block growth and sales growth in the group life product line.

Net investment income was higher compared to 2021 due to higher investment income from inflation index-linked bonds.

The benefit ratio, excluding the reserve assumption updates, was favorable relative to 2021 due to lower mortality in the group life product line and higher discount rates on new claims in the group long-term disability product line, partially offset by higher inflation-linked experience for our group life and group long-term disability products and higher claims incidence in the supplemental product line and in the group long-term disability product line.

Commissions increased relative to 2021 due primarily to in-force block growth. The deferral of acquisition costs and the amortization of deferred acquisition costs were generally consistent relative to 2021. The other expense ratio was higher relative to 2021 due to an increase in employee-related costs and operational investments in the business.

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Sales

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The following discussion of sales results relates only to our Unum UK product lines and is based on functional currency.

Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

Group long-term disability sales increased compared to 2022 driven by higher sales to new customers in the core market, which we define as employee groups with fewer than 500 employees, and an increase in sales to new and existing customers in the large case market.

Group life sales increased compared to 2022 driven by higher sales to new and existing customers in the core market, and higher sales to existing customers in the large case market.

Supplemental sales increased compared to 2022 due primarily to higher sales in the group critical illness and dental product lines.

Year Ended December 31, 2022 Compared with Year Ended December 31, 2021

Group long-term disability sales increased compared to 2021 driven by higher sales to new customers in the large case market and existing customers in the core market, partially offset by lower sales to new customers in the core market.

Group life sales increased compared to 2021 driven primarily by higher sales to new customers in both the large case and core markets.

Supplemental sales increased compared to 2021 due primarily to higher sales in the dental product line, partially offset by lower sales in the group critical illness product line.

Goodwill

We had total goodwill of $42.2 million for the Unum International segment at December 31, 2023, of which, $37.4 million is attributed to the Unum UK reporting unit and $4.8 million is attributed to the Unum Poland reporting unit, none of which is currently believed to be at risk for future impairment.

Segment Outlook

We are committed to driving growth in the Unum International segment and will build on the capabilities that we believe will generate growth and profitability in our businesses over the long term. In 2024, we will focus on scaling our business and broadening our international portfolio. For our Unum UK line of business, achieving growth remains a priority, and we will continue to focus on delivering a best in class health and wellbeing service to improve retention of our key customers and drive growth across our product offerings. We will also accelerate premium growth by focusing on both the broker experience and customer engagement, while maintaining our disciplined approach to pricing. Within our Unum Poland line of business, we will drive growth by expanding our distribution and the direct to employer channel. We will also continue to invest in digital capabilities, technology, and product enhancements which we believe will drive sustainable growth over the long term.

In 2024, we expect sales and premium growth to continue, alongside stable claim experience. We recognize that 2023 earnings benefited from inflation linked income, which we expect will continue to decrease in 2024 and could pressure earnings growth. We may see impacts to net investment income and fluctuations in our benefit ratio as inflation continues to moderate. We continuously monitor key indicators to assess our risks and adjust our business plans accordingly.

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Colonial Life Segment

The Colonial Life segment includes insurance for accident, sickness, and disability products, which includes dental and vision products, life products, and cancer and critical illness products. These products are marketed to employees, on both a group and an individual basis, at the workplace through an independent contractor agent sales force and brokers.

Operating Results

Shown below are financial results and key performance indicators for the Colonial Life segment.

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Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

Premium income was favorable compared to 2022 due to higher prior period sales, particularly in the life product line, and favorable persistency. Net investment income was generally consistent in 2023 compared to 2022 with an increase in the level of invested assets and an increase in the yield on invested assets, mostly offset by lower miscellaneous investment income.

The benefit ratio, excluding the impacts of the reserve assumption updates, was favorable relative to 2022 due primarily to lower claim costs in the cancer and critical illness product line and favorable mortality experience as a result of lessening impacts of COVID-19 on our insured population in the life product line, partially offset by an increase in reserves due to model refinements in the life product line.

Commissions and the deferral of acquisition costs were higher compared to 2022 due to higher prior period sales. The amortization of deferred acquisition costs was higher compared to 2022 primarily due to growth in the level of the deferred asset and the impact of the policyholder lapses. The other expense ratio was higher relative to 2022 due primarily to an increase in employee-related costs and an increase in operational investments in our business.

Year Ended December 31, 2022 Compared with Year Ended December 31, 2021

Premium income was favorable compared to 2021 due to higher prior period sales, partially offset by lower overall persistency. Net investment income was lower in 2022 compared to 2021 due to lower miscellaneous investment income and a decline in the yield on invested assets, partially offset by an increase in the level of invested assets.

The benefit ratio, excluding the impacts of the reserve assumption updates, was favorable relative to 2021 across all product lines, including the life product line as a result of the lessening impacts of COVID-19 on our insured population.

Commissions and the deferral of acquisition costs were higher compared to 2021 due to higher prior period sales. The amortization of deferred acquisition costs was higher compared to 2021 due to higher policyholder lapses primarily in the accident, sickness, and disability product line. The other expense ratio was higher relative to 2021 due primarily to an increase in the operational investments in our business, an increase in employee-related costs, and a decrease in the allowance for expected credit losses during 2021 that did not recur in 2022.

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Sales

Year Ended December 31, 2023 Compared with Year Ended December 31, 2022

During 2023, we have seen an increase in sales for each of our product lines relative to 2022. Commercial market sales increased compared to 2022 driven by higher sales to new and existing customers in the core market, which we define as accounts with fewer than 1,000 employees, and higher sales to new and existing customers in the large case market. Public sector market sales increased compared to 2022 due to higher sales to existing customers.

Year Ended December 31, 2022 Compared with Year Ended December 31, 2021

During 2022, we saw an increase in sales for each of our product lines relative to 2021. Commercial market sales increased compared to 2021 driven by higher sales to existing customers in the core market partially offset by lower sales to new and existing customers in the large case market. Public sector market sales increased compared to 2021 due to higher sales to both new and existing customers.

Goodwill

We had goodwill of $27.7 million at December 31, 2023, none of which is currently believed to be at risk for future impairment.

Segment Outlook

We remain committed to providing employees and their families with simple, modern, and personal benefit solutions. During 2024, we will continue to utilize our strong distribution system of independent agents, benefit counselors and broker partnerships. We will also continue to invest in solutions and digital capabilities to expand our reach and effectiveness, driving growth and improving productivity while enhancing the customer experience. In 2024, we will continue to bring an enhanced engagement and enrollment platform to market, enabling deeper connections with employees through the enrollment process as well as maintaining stronger relationships throughout the customer lifecycle. We believe our distribution system, customer service capabilities, digital and virtual tools, and ability to serve all market sizes position us well for future growth.

In 2024, we expect strong growth in adjusted operating income for the full year with sales and premium growth increasing from the prior year. We expect improved claim experience in 2024 but could continue to experience some level of claims volatility. While we believe our underlying profitability will remain strong, current economic conditions and increasing competition in the voluntary workplace market are risks to achievement of our business plans. We continuously monitor key indicators to assess our risks and adjust our business plans accordingly.

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Closed Block Segment

The Closed Block segment consists of group and individual long-term care and other insurance products no longer actively marketed. We discontinued offering individual long-term care in 2009 and group long-term care in 2012. Other insurance products include individual disability, group pension, individual life and corporate-owned life insurance, reinsurance pools and management operations, and other miscellaneous product lines.

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Operating Results

Shown below are financial results and key performance indicators for the Closed Block segment.