Investments | 5. Investments Fixed Maturity Securities Available-for-Sale Fixed Maturity Securities Available-for-Sale by Sector The following table presents the fixed maturity securities available-for-sale (“AFS”) by sector. U.S. corporate and foreign corporate sectors include redeemable preferred stock. Residential mortgage-backed securities (“RMBS”) includes agency, prime, alternative and sub-prime mortgage-backed securities. Asset-backed securities (“ABS”) includes securities collateralized by corporate loans and consumer loans. Municipals includes taxable and tax-exempt revenue bonds and, to a much lesser extent, general obligations of states, municipalities and political subdivisions. Commercial mortgage-backed securities (“CMBS”) primarily includes securities collateralized by multiple commercial mortgage loans. RMBS, ABS and CMBS are, collectively, “Structured Products.” March 31, 2021 December 31, 2020 Amortized Gross Unrealized Estimated Amortized Gross Unrealized Estimated Sector Allowance for Gains Losses Allowance for Gains Losses (In millions) U.S. corporate $ 50,650 $ (43) $ 6,432 $ 251 $ 56,788 $ 50,989 $ (43) $ 9,618 $ 155 $ 60,409 Foreign corporate 27,816 (17) 3,033 305 30,527 28,093 (8) 4,478 284 32,279 U.S. government and agency 25,120 — 3,589 208 28,501 24,620 — 6,178 27 30,771 RMBS 21,957 — 1,452 135 23,274 22,552 — 1,706 32 24,226 ABS 11,930 — 146 27 12,049 12,456 — 169 50 12,575 Municipals 6,867 — 1,549 29 8,387 6,888 — 2,096 1 8,983 CMBS 6,451 (6) 285 45 6,685 6,503 — 381 55 6,829 Foreign government 4,332 — 713 63 4,982 4,322 — 978 32 5,268 Total fixed maturity securities AFS $ 155,123 $ (66) $ 17,199 $ 1,063 $ 171,193 $ 156,423 $ (51) $ 25,604 $ 636 $ 181,340 Maturities of Fixed Maturity Securities AFS The amortized cost, net of allowance for credit loss (“ACL”), and estimated fair value of fixed maturity securities AFS, by contractual maturity date, were as follows at March 31, 2021: Due in One Due After Due After Due After Structured Total Fixed (In millions) Amortized cost, net of ACL $ 6,532 $ 23,971 $ 26,937 $ 57,285 $ 40,332 $ 155,057 Estimated fair value $ 6,542 $ 25,113 $ 30,046 $ 67,484 $ 42,008 $ 171,193 Actual maturities may differ from contractual maturities due to the exercise of call or prepayment options. Fixed maturity securities AFS not due at a single maturity date have been presented in the year of final contractual maturity. Structured Products are shown separately, as they are not due at a single maturity. Continuous Gross Unrealized Losses for Fixed Maturity Securities AFS by Sector The following table presents the estimated fair value and gross unrealized losses of fixed maturity securities AFS in an unrealized loss position without an ACL by sector and aggregated by length of time that the securities have been in a continuous unrealized loss position. March 31, 2021 December 31, 2020 Less than 12 Months Equal to or Greater Less than 12 Months Equal to or Greater Sector & Credit Quality Estimated Gross Estimated Gross Estimated Gross Estimated Gross (Dollars in millions) U.S. corporate $ 3,671 $ 161 $ 883 $ 81 $ 2,351 $ 112 $ 230 $ 36 Foreign corporate 2,751 169 847 136 2,431 225 34 59 U.S. government and agency 5,354 208 — — 1,686 27 — — RMBS 4,425 119 412 16 1,119 20 128 12 ABS 1,898 11 899 16 2,561 18 2,233 32 Municipals 542 29 — — 51 1 — — CMBS 927 21 559 24 1,110 41 306 14 Foreign government 372 31 121 31 110 6 115 27 Total fixed maturity securities AFS $ 19,940 $ 749 $ 3,721 $ 304 $ 11,419 $ 450 $ 3,046 $ 180 Investment grade $ 18,278 $ 693 $ 2,515 $ 188 $ 9,012 $ 297 $ 2,841 $ 158 Below investment grade 1,662 56 1,206 116 2,407 153 205 22 Total fixed maturity securities AFS $ 19,940 $ 749 $ 3,721 $ 304 $ 11,419 $ 450 $ 3,046 $ 180 Total number of securities in an 1,797 472 984 385 Evaluation of Fixed Maturity Securities AFS for Credit Loss Evaluation and Measurement Methodologies Management considers a wide range of factors about the security issuer and uses its best judgment in evaluating the cause of the decline in the estimated fair value of the security and in assessing the prospects for near-term recovery. Inherent in management’s evaluation of the security are assumptions and estimates about the operations of the issuer and its future earnings potential. Considerations used in the credit loss evaluation process include, but are not limited to: (i) the extent to which the estimated fair value has been below amortized cost, (ii) adverse conditions specifically related to a security, an industry sector or sub-sector, or an economically depressed geographic area, adverse change in the financial condition of the issuer of the security, changes in technology, discontinuance of a segment of the business that may affect future earnings, and changes in the quality of credit enhancement, (iii) payment structure of the security and likelihood of the issuer being able to make payments, (iv) failure of the issuer to make scheduled interest and principal payments, (v) whether the issuer, or series of issuers or an industry has suffered a catastrophic loss or has exhausted natural resources, (vi) whether the Company has the intent to sell or will more likely than not be required to sell a particular security before the decline in estimated fair value below amortized cost recovers, (vii) with respect to Structured Products, changes in forecasted cash flows after considering the changes in the financial condition of the underlying loan obligors and quality of underlying collateral, expected prepayment speeds, current and forecasted loss severity, consideration of the payment terms of the underlying assets backing a particular security, and the payment priority within the tranche structure of the security, (viii) changes in the rating of the security by a rating agency, and (ix) other subjective factors, including concentrations and information obtained from regulators. The methodology and significant inputs used to determine the amount of credit loss are as follows: • The Company calculates the recovery value by performing a discounted cash flow analysis based on the present value of future cash flows. The discount rate is generally the effective interest rate of the security at the time of purchase for fixed-rate securities and the spot rate at the date of evaluation of credit loss for floating-rate securities. • When determining collectability and the period over which value is expected to recover, the Company applies considerations utilized in its overall credit loss evaluation process which incorporates information regarding the specific security, fundamentals of the industry and geographic area in which the security issuer operates, and overall macroeconomic conditions. Projected future cash flows are estimated using assumptions derived from management’s single best estimate, the most likely outcome in a range of possible outcomes, after giving consideration to a variety of variables that include, but are not limited to: payment terms of the security; the likelihood that the issuer can service the interest and principal payments; the quality and amount of any credit enhancements; the security’s position within the capital structure of the issuer; possible corporate restructurings or asset sales by the issuer; any private and public sector programs to restructure foreign government securities and municipals; and changes to the rating of the security or the issuer by rating agencies. • Additional considerations are made when assessing the unique features that apply to certain Structured Products including, but not limited to: the quality of underlying collateral, historical performance of the underlying loan obligors, historical rent and vacancy levels, changes in the financial condition of the underlying loan obligors, expected prepayment speeds, current and forecasted loss severity, consideration of the payment terms of the underlying loans or assets backing a particular security, changes in the quality of credit enhancement and the payment priority within the tranche structure of the security. With respect to securities that have attributes of debt and equity (“perpetual hybrid securities”), consideration is given in the credit loss analysis as to whether there has been any deterioration in the credit of the issuer and the likelihood of recovery in value of the securities that are in a severe unrealized loss position. Consideration is also given as to whether any perpetual hybrid securities with an unrealized loss, regardless of credit rating, have deferred any dividend payments. In periods subsequent to the recognition of an initial ACL on a security, the Company reassesses credit loss quarterly. Subsequent increases or decreases in the expected cash flow from the security result in corresponding decreases or increases in the ACL which are recorded within net investment gains (losses); however, the previously recorded ACL is not reduced to an amount below zero. Full or partial write-offs are deducted from the ACL in the period the security, or a portion thereof, is considered uncollectible. Recoveries of amounts previously written off are recorded to the ACL in the period received. When the Company has the intent to sell the security or it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost, any ACL is written off and the amortized cost is written down to estimated fair value through a charge within net investment gains (losses), which becomes the new amortized cost of the security. Evaluation of Fixed Maturity Securities AFS in an Unrealized Loss Position Gross unrealized losses on securities without an ACL increased $423 million for the three months ended March 31, 2021 to $1.1 billion primarily due to increases in interest rates, partially offset by narrowing credit spreads. Gross unrealized losses on securities without an ACL that have been in a continuous gross unrealized loss position for 12 months or greater were $304 million at March 31, 2021, or 29% of the total gross unrealized losses on securities without an ACL. Investment Grade Fixed Maturity Securities AFS Of the $304 million of gross unrealized losses on securities without an ACL that have been in a continuous gross unrealized loss position for 12 months or greater, $188 million, or 62%, were related to 331 investment grade securities. Unrealized losses on investment grade securities are principally related to widening credit spreads since purchase and, with respect to fixed-rate securities, rising interest rates since purchase. Below Investment Grade Fixed Maturity Securities AFS Of the $304 million of gross unrealized losses on securities without an ACL that have been in a continuous gross unrealized loss position for 12 months or greater, $116 million, or 38%, were related to 141 below investment grade securities. Unrealized losses on below investment grade securities are principally related to U.S. and foreign corporate securities (primarily industrial and consumer) and CMBS and are the result of significantly wider credit spreads resulting from higher risk premiums since purchase, largely due to economic and market uncertainty, as well as with respect to fixed-rate securities, rising interest rates since purchase. Management evaluates U.S. corporate and foreign corporate securities based on factors such as expected cash flows, financial condition and near-term and long-term prospects of the issuers. Management evaluates CMBS based on actual and projected cash flows after considering the quality of underlying collateral, credit enhancements, expected prepayment speeds, current and forecasted loss severity, the payment terms of the underlying assets backing a particular security and the payment priority within the tranche structure of the security. Current Period Evaluation At March 31, 2021, with respect to securities in an unrealized loss position without an ACL, the Company did not intend to sell these securities, and it was not more likely than not that the Company would be required to sell these securities before the anticipated recovery of the remaining amortized cost. Based on the Company’s current evaluation of its securities in an unrealized loss position without an ACL, the Company concluded that these securities had not incurred a credit loss and should not have an ACL at March 31, 2021. Future provisions for credit loss will depend primarily on economic fundamentals, issuer performance (including changes in the present value of future cash flows expected to be collected), changes in credit ratings and collateral valuation. Mortgage Loans Mortgage Loans by Portfolio Segment Mortgage loans are summarized as follows at: March 31, 2021 December 31, 2020 Portfolio Segment Carrying % of Carrying % of (Dollars in millions) Mortgage loans: Commercial $ 38,013 58.6% $ 38,528 58.0% Agricultural 16,042 24.7 16,426 24.7 Residential 11,169 17.2 11,803 17.8 Total amortized cost 65,224 100.5 66,757 100.5 Allowance for credit loss (455) (0.7) (517) (0.8) Subtotal mortgage loans, net 64,769 99.8 66,240 99.7 Residential — FVO 149 0.2 165 0.3 Total mortgage loans, net $ 64,918 100.0% $ 66,405 100.0% The Company elects the FVO for certain residential mortgage loans that are managed on a total return basis. See Note 7 for further information. The amount of net discounts, included within total amortized cost, primarily attributable to residential mortgage loans was $888 million and $924 million at March 31, 2021 and December 31, 2020, respectively. The accrued interest income excluded from total amortized cost for commercial, agricultural and residential mortgage loans at March 31, 2021 and December 31, 2020 was $157 million and $164 million; $117 million and $158 million; and $100 million and $101 million, respectively. Purchases of mortgage loans, primarily residential, were $377 million and $1.0 billion for the three months ended March 31, 2021 and 2020, respectively. See “— Related Party Investment Transactions” for information regarding transfers from affiliates. Allowance for Credit Loss Rollforward by Portfolio Segment The changes in the ACL, by portfolio segment, were as follows: Three Months Ended March 31, 2021 2020 Commercial Agricultural Residential Total Commercial Agricultural Residential Total (In millions) Balance, beginning of period $ 199 $ 97 $ 221 $ 517 $ 186 $ 49 $ 54 $ 289 Provision (release) (7) (13) (29) (49) 14 (5) 23 32 Adoption of credit loss guidance — — — — (87) 32 154 99 Charge-offs, net of recoveries — (13) — (13) — — (3) (3) Balance, end of period $ 192 $ 71 $ 192 $ 455 $ 113 $ 76 $ 228 $ 417 Allowance for Credit Loss Methodology The Company records an allowance for expected lifetime credit loss in an amount that represents the portion of the amortized cost basis of mortgage loans that the Company does not expect to collect, resulting in mortgage loans being presented at the net amount expected to be collected. In determining the Company’s ACL, management: (i) pools mortgage loans that share similar risk characteristics, (ii) considers expected lifetime credit loss over the contractual term of its mortgage loans adjusted for expected prepayments and any extensions, and (iii) considers past events and current and forecasted economic conditions. Each of the Company’s commercial, agricultural and residential mortgage loan portfolio segments are evaluated separately. The ACL is calculated for each mortgage loan portfolio segment based on inputs unique to each loan portfolio segment. On a quarterly basis, mortgage loans within a portfolio segment that share similar risk characteristics, such as internal risk ratings or consumer credit scores, are pooled for calculation of ACL. On an ongoing basis, mortgage loans with dissimilar risk characteristics (i.e., loans with significant declines in credit quality), collateral dependent mortgage loans (i.e., when the borrower is experiencing financial difficulty, including when foreclosure is reasonably possible or probable) and reasonably expected troubled debt restructurings (“TDRs”) (i.e., the Company grants concessions to borrower that is experiencing financial difficulties) are evaluated individually for credit loss. The ACL for loans evaluated individually are established using the same methodologies for all three portfolio segments. For example, the ACL for a collateral dependent loan is established as the excess of amortized cost over the estimated fair value of the loan’s underlying collateral, less selling cost when foreclosure is probable. Accordingly, the change in the estimated fair value of collateral dependent loans, which are evaluated individually for credit loss, is recorded as a change in the ACL which is recorded on a quarterly basis as a charge or credit to earnings in net investment gains (losses). Commercial and Agricultural Mortgage Loan Portfolio Segments Commercial and agricultural mortgage loan ACL are calculated in a similar manner. Within each loan portfolio segment, commercial and agricultural, loans are pooled by internal risk rating. Estimated lifetime loss rates, which vary by internal risk rating, are applied to the amortized cost of each loan, excluding accrued investment income, on a quarterly basis to develop the ACL. Internal risk ratings are based on an assessment of the loan’s credit quality, which can change over time. The estimated lifetime loss rates are based on several loan portfolio segment-specific factors, including (i) the Company’s experience with defaults and loss severity, (ii) expected default and loss severity over the forecast period, (iii) current and forecasted economic conditions including growth, inflation, interest rates and unemployment levels, (iv) loan specific characteristics including loan-to-value (“LTV”) ratios, and (v) internal risk ratings. These evaluations are revised as conditions change and new information becomes available. The Company uses its several decades of historical default and loss severity experience which capture multiple economic cycles. The Company uses a forecast of economic assumptions for a two-year period for most of its commercial and agricultural mortgage loans, while a one-year period is used for loans originated in certain markets. After the applicable forecast period, the Company reverts to its historical loss experience using a straight-line basis over two years. For evaluations of commercial mortgage loans, in addition to historical experience, management considers factors that include the impact of a rapid change to the economy, which may not be reflected in the loan portfolio, recent loss and recovery trend experience as compared to historical loss and recovery experience, and loan specific characteristics including debt service coverage ratios (“DSCR”). In estimating expected lifetime credit loss over the term of its commercial mortgage loans, the Company adjusts for expected prepayment and extension experience during the forecast period using historical prepayment and extension experience considering the expected position in the economic cycle and the loan profile (i.e., floating rate, shorter-term fixed rate and longer-term fixed rate) and after the forecast period using long-term historical prepayment experience. For evaluations of agricultural mortgage loans, in addition to historical experience, management considers factors that include increased stress in certain sectors, which may be evidenced by higher delinquency rates, or a change in the number of higher risk loans. In estimating expected lifetime credit loss over the term of its agricultural mortgage loans, the Company’s experience is much less sensitive to the position in the economic cycle and by loan profile; accordingly, historical prepayment experience is used, while extension terms are not prevalent with the Company’s agricultural mortgage loans. Commercial mortgage loans are reviewed on an ongoing basis, which review includes, but is not limited to, an analysis of the property financial statements and rent roll, lease rollover analysis, property inspections, market analysis, estimated valuations of the underlying collateral, LTV ratios, DSCR and tenant creditworthiness. The monitoring process focuses on higher risk loans, which include those that are classified as restructured, delinquent or in foreclosure, as well as loans with higher LTV ratios and lower DSCR. Agricultural mortgage loans are reviewed on an ongoing basis, which review includes, but is not limited to, property inspections, market analysis, estimated valuations of the underlying collateral, LTV ratios and borrower creditworthiness, as well as reviews on a geographic and property-type basis. The monitoring process for agricultural mortgage loans also focuses on higher risk loans. For commercial mortgage loans, the primary credit quality indicator is the DSCR, which compares a property’s net operating income to amounts needed to service the principal and interest due under the loan. Generally, the lower the DSCR, the higher the risk of experiencing a credit loss. The Company also reviews the LTV ratio of its commercial mortgage loan portfolio. LTV ratios compare the unpaid principal balance of the loan to the estimated fair value of the underlying collateral. Generally, the higher the LTV ratio, the higher the risk of experiencing a credit loss. The DSCR and the values utilized in calculating the ratio are updated routinely. In addition, the LTV ratio is routinely updated for all but the lowest risk loans as part of the Company’s ongoing review of its commercial mortgage loan portfolio. For agricultural mortgage loans, the Company’s primary credit quality indicator is the LTV ratio. The values utilized in calculating this ratio are developed in connection with the ongoing review of the agricultural mortgage loan portfolio and are routinely updated. Commitments to lend: After loans are approved, the Company makes commitments to lend and, typically, borrowers draw down on some or all of the commitments. The timing of mortgage loan funding is based on the commitment expiration dates. A liability for credit loss for unfunded commercial and agricultural mortgage loan commitments is recorded within net investment gains (losses). The liability is based on estimated lifetime loss rates as described above and the amount of the outstanding commitments, which for lines of credit, considers estimated utilization rates. When the commitment is funded or expires, the liability is adjusted accordingly. Residential Mortgage Loan Portfolio Segment The Company’s residential mortgage loan portfolio is comprised primarily of purchased closed end, amortizing residential mortgage loans, including both performing loans purchased within 12 months of origination and reperforming loans purchased after they have been performing for at least 12 months post-modification. Residential mortgage loans are pooled by loan type (i.e., new origination and reperforming) and pooled by similar risk profiles (including consumer credit score and LTV ratios). Estimated lifetime loss rates, which vary by loan type and risk profile, are applied to the amortized cost of each loan excluding accrued investment income on a quarterly basis to develop the ACL. The estimated lifetime loss rates are based on several factors, including (i) industry historical experience and expected results over the forecast period for defaults, (ii) loss severity, (iii) prepayment rates, (iv) current and forecasted economic conditions including growth, inflation, interest rates and unemployment levels, and (v) loan pool specific characteristics including consumer credit scores, LTV ratios, payment history and home prices. These evaluations are revised as conditions change and new information becomes available. The Company uses industry historical experience which captures multiple economic cycles as the Company has purchased most of its residential mortgage loans in the last five years. The Company uses a forecast of economic assumptions for a two-year period for most of its residential mortgage loans. After the applicable forecast period, the Company immediately reverts to industry historical loss experience. For residential mortgage loans, the Company’s primary credit quality indicator is whether the loan is performing or nonperforming. The Company generally defines nonperforming residential mortgage loans as those that are 60 or more days past due and/or in nonaccrual status which is assessed monthly. Generally, nonperforming residential mortgage loans have a higher risk of experiencing a credit loss. Mortgage Loan Concessions In response to the adverse economic impact of the COVID-19 Pandemic, in 2021 and 2020, the Company granted concessions to certain of its commercial, agricultural and residential mortgage loan borrowers, including payment deferrals and other loan modifications. The Company has elected the option under the Coronavirus Aid, Relief, and Economic Security Act, the Consolidated Appropriations Act, 2021 and the Interagency Statement on Loan Modifications and Reporting for Financial Institutions Working with Customers Affected by the Coronavirus (Revised) issued by bank regulatory agencies, not to account for or report qualifying concessions as TDRs and not to classify such loans as either past due or nonaccrual during the payment deferral period. Additionally, in accordance with the FASB’s published response to a COVID-19 Pandemic technical inquiry, the Company continues to accrue interest income on such loans that have deferred payment. The Company records an ACL on this accrued interest income. Commercial For some commercial mortgage loan borrowers (principally in the retail and hotel sectors), the Company granted concessions which were primarily interest and principal payment deferrals generally ranging from three to four months and, to a much lesser extent, maturity date extensions. Deferred commercial mortgage loan interest and principal payments were $42 million at March 31, 2021. Agricultural For some agricultural mortgage loan borrowers (principally in the annual crops and agribusiness sectors), the Company granted concessions which were primarily principal payment deferrals generally ranging from three to 12 months, and covenant changes and, to a much lesser extent, maturity date extensions. Deferred agricultural mortgage loan interest and principal payments were $8 million at March 31, 2021. Residential For some residential mortgage loan borrowers, the Company granted concessions which were primarily three-month interest and principal payment deferrals. Deferred residential mortgage loan interest and principal payments were $31 million at March 31, 2021. Credit Quality of Mortgage Loans by Portfolio Segment The amortized cost of commercial mortgage loans by credit quality indicator and vintage year was as follows at March 31, 2021: Credit Quality Indicator 2021 2020 2019 2018 2017 Prior Revolving Total % of (Dollars in millions) LTV ratios: Less than 65% $ 444 $ 3,211 $ 2,487 $ 3,796 $ 2,764 $ 11,406 $ 2,291 $ 26,399 69.4 % 65% to 75% 206 946 2,799 1,717 1,135 2,229 — 9,032 23.8 76% to 80% 47 — 130 65 388 495 — 1,125 3.0 Greater than 80% 5 — — 49 421 982 — 1,457 3.8 Total $ 702 $ 4,157 $ 5,416 $ 5,627 $ 4,708 $ 15,112 $ 2,291 $ 38,013 100.0 % DSCR: > 1.20x $ 702 $ 3,753 $ 5,057 $ 5,609 $ 4,401 $ 13,741 $ 2,291 $ 35,554 93.5 % 1.00x - 1.20x — 213 — 18 188 844 — 1,263 3.3 <1.00x — 191 359 — 119 527 — 1,196 3.2 Total $ 702 $ 4,157 $ 5,416 $ 5,627 $ 4,708 $ 15,112 $ 2,291 $ 38,013 100.0 % The amortized cost of agricultural mortgage loans by credit quality indicator and vintage year was as follows at March 31, 2021: Credit Quality Indicator 2021 2020 2019 2018 2017 Prior Revolving Total % of (Dollars in millions) LTV ratios: Less than 65% $ 155 $ 2,333 $ 1,996 $ 2,593 $ 973 $ 5,623 $ 900 $ 14,573 90.8 % 65% to 75% 143 336 139 35 38 586 99 1,376 8.6 76% to 80% — — — — — 51 — 51 0.3 Greater than 80% — — — — — 42 — 42 0.3 Total $ 298 $ 2,669 $ 2,135 $ 2,628 $ 1,011 $ 6,302 $ 999 $ 16,042 100.0 % The amortized cost of residential mortgage loans by credit quality indicator and vintage year was as follows at March 31, 2021: Credit Quality Indicator 2021 2020 2019 2018 2017 Prior Revolving Total % of (Dollars in millions) Performance indicators: Performing $ 5 $ 293 $ 1,450 $ 755 $ 333 $ 7,843 $ — $ 10,679 95.6 % Nonperforming (1) — 3 39 11 6 431 — 490 4.4 Total $ 5 $ 296 $ 1,489 $ 766 $ 339 $ 8,274 $ — $ 11,169 100.0 % __________________ (1) Includes residential mortgage loans in process of foreclosure of $93 million and $102 million at March 31, 2021 and December 31, 2020, respectively. LTV ratios compare the unpaid principal balance of the loan to the estimated fair value of the underlying collateral. At March 31, 2021, the amortized cost of commercial and agricultural mortgage loans with a LTV ratio in excess of 100% was $522 million, or less than 1% of total commercial and agricultural mortgage loans, however after considering the reduction in carrying value from the related ACL, no loans have a ratio greater than 100%. Past Due and Nonaccrual Mortgage Loans The Company has a high quality, well performing mortgage loan portfolio, with 99% of all mortgage loans classified as performing at both March 31, 2021 and December 31, 2020. The Company defines delinquency consistent with industry practice, when mortgage loans are past due more than two or more months, as applicable, by portfolio segment. The past due and nonaccrual mortgage loans at amortized cost, prior to ACL, by portfolio segment, were as follows: Past Due Greater than 90 Days Past Due Nonaccrual Portfolio Segment March 31, 2021 December 31, 2020 March 31, 2021 December 31, 2020 March 31, 2021 December 31, 2020 (In millions) Commercial $ — $ — $ — $ — $ 127 $ 293 Agricultural 229 251 5 20 259 261 Residential 490 516 4 54 488 503 Total $ 719 $ 767 $ 9 $ 74 $ 874 $ 1,057 The amortized cost for nonaccrual commercial, agricultural and residential mortgage loans at beginning of year 2020 was $167 million, $137 million and $377 million, respectively. The amortized cost for nonaccrual commercial mortgage loans with no ACL was $0 and $156 million at March 31, 2021 and December 31, 2020, respectively. The amortized cost for nonaccrual agricultural mortgage loans with no ACL was $192 million and $173 million at March 31, 2021 and December 31, 2020, respectively. There were no nonaccrual residential mortgage loans without an ACL at either March 31, 2021 or December 31, 2020. Real Estate and Real Estate Joint Ventures The Company’s real estate investment portfolio is diversified by property type, geography and income stream, including income from operating leases, operating income and equity in earnings from equity method real estate joint ventures. Real estate investments, by income type, as well as income earned, were as follows at and for the periods indicated: March 31, 2021 December 31, 2020 Three Months 2021 2020 Income Type Carrying Value Income (In millions) Leased real estate investments $ 2,105 $ 1,965 $ 54 $ 46 Other real estate investments 424 418 34 34 Real estate joint ventures 5,230 5,095 6 7 Total real estate and real estate joint ventures $ 7,759 $ 7,478 $ 94 $ 87 The carrying value of real estate investments acquired through foreclosure was $189 million and $18 million at March 31, 2021 and December 31, 2020, respectively. Depreciation expense on real estate investments was $21 million and $16 million for the three months ended March 31, 2021 and 2020, respectively. Real estate investments were net of accumulated depreciation of $787 million and $789 million at March 31, 2021 and December 31, 2020, respectively. Leases Leased Real Estate Investments - Operating Leases The Company, as lessor, leases investment real estate, principally commercial real estate for office and retail use, through a variety of operating lease arrangements, which typically include tenant reimbursement for property operating costs and options to renew or extend the lease. In some circumstances, leases may include an option for the lessee to purchase the property. In addition, certain leases of retail space may stipulate that a portion of the income earned is contingent upon the level of the tenants’ revenues. The Company has elected a practical expedient of not separating non-lease components related to reimbursement of property operating costs from associated lease components. These property operating costs have the same timing and pattern of transfer as the related lease component, because they are incurred over the same period of time as the operating lease. Therefore, the combin |