Mortgage-Backed and Credit Risk Transfer Securities | Mortgage-Backed and Credit Risk Transfer Securities During the first half of 2020, we experienced unprecedented market conditions as a result of the COVID-19 pandemic and sold a substantial portion of our MBS and GSE CRT portfolio to generate liquidity and reduce leverage. We resumed investing in Agency RMBS in July 2020. The following tables summarize our MBS portfolio by asset type as of June 30, 2021 and December 31, 2020. June 30, 2021 $ in thousands Principal/ Notional Unamortized Amortized Unrealized Fair Period- end Weighted Average Yield (1) Agency RMBS: 30 year fixed-rate 8,381,884 257,610 8,639,494 3,336 8,642,830 2.04 % Total Agency RMBS pass-through 8,381,884 257,610 8,639,494 3,336 8,642,830 2.04 % Agency-CMO (2) 116,495 (101,995) 14,500 (299) 14,201 7.33 % Non-Agency CMBS 61,427 (4,070) 57,357 6,443 63,800 8.75 % Non-Agency RMBS (3)(4)(5) 521,837 (512,027) 9,810 22 9,832 10.02 % Total 9,081,643 (360,482) 8,721,161 9,502 8,730,663 2.10 % (1) Period-end weighted average yield is based on amortized cost as of June 30, 2021 and incorporates future prepayment and loss assumptions. (2) Agency collateralized mortgage obligation ("Agency-CMO") are interest-only securities ("Agency IO"). (3) Non-Agency RMBS is 64.5% fixed rate, 34.5% variable rate, and 1.0% floating rate based on fair value. Coupon payments on variable rate investments are based upon changes in the underlying Hybrid adjustable-rate mortgage ("ARM") loan coupons, while coupon payments on floating rate investments are based upon a spread to a reference index. (4) Of the total discount in non-Agency RMBS, $2.1 million is non-accretable (calculated using the principal/notional balance) based on estimated future cash flows of the securities. (5) Non-Agency RMBS includes interest-only securities ("non-Agency IO") which represent 98.2% of principal/notional balance, 47.0% of amortized cost and 30.0% of fair value. December 31, 2020 $ in thousands Principal/Notional Unamortized Amortized Allowance for Credit Losses Unrealized Fair Period- end Weighted Average Yield (1) Agency RMBS: 30 year fixed-rate 7,635,107 391,644 8,026,751 — 24,115 8,050,866 1.86 % Total Agency RMBS pass-through 7,635,107 391,644 8,026,751 — 24,115 8,050,866 1.86 % Agency-CMO (2) 19,634 (19,634) — — — — — % Non-Agency CMBS 112,549 (5,791) 106,758 (1,768) 4,593 109,583 9.40 % Non-Agency RMBS (3)(4)(5) 790,627 (779,660) 10,967 — 766 11,733 7.83 % Total 8,557,917 (413,441) 8,144,476 (1,768) 29,474 8,172,182 1.97 % (1) Period-end weighted average yield is based on amortized cost as of December 31, 2020 and incorporates future prepayment and loss assumptions. (2) All Agency-CMO are Agency IO. (3) Non-Agency RMBS is 67.3% fixed rate, 31.8% variable rate and 0.9% floating rate based on fair value. Coupon payments on variable rate investments are based upon changes in the underlying Hybrid ARM loan coupons, while coupon payments on floating rate investments are based upon a spread to a reference index. (4) Of the total discount in non-Agency RMBS, $2.1 million is non-accretable calculated using the principal/notional balance based on estimated future cash flows of the securities. (5) Non-Agency RMBS includes non-Agency IO which represent 98.8% of principal/notional balance, 49.3% of amortized cost and 41.5% of fair value. The following table presents the fair value of our available-for-sale securities and securities accounted for under the fair value option by asset type as of June 30, 2021 and December 31, 2020. We have elected the fair value option for all of our RMBS interest-only securities and our MBS purchased on or after September 1, 2016. As of June 30, 2021 and December 31, 2020, approximately 99% of our MBS are accounted for under the fair value option. June 30, 2021 December 31, 2020 $ in thousands Available-for-sale Securities Securities under Fair Value Option Total Available-for-sale Securities Securities under Fair Value Option Total Agency RMBS: 30 year fixed-rate — 8,642,830 8,642,830 — 8,050,866 8,050,866 Total RMBS Agency pass-through — 8,642,830 8,642,830 — 8,050,866 8,050,866 Agency-CMO — 14,201 14,201 — — — Non-Agency CMBS 63,800 — 63,800 109,583 — 109,583 Non-Agency RMBS 7,078 2,754 9,832 7,267 4,466 11,733 Total 70,878 8,659,785 8,730,663 116,850 8,055,332 8,172,182 The components of the carrying value of our MBS portfolio at June 30, 2021 and December 31, 2020 are presented below. Accrued interest receivable on our MBS portfolio, which is recorded within investment related receivable on our condensed consolidated balance sheets, was $17.3 million at June 30, 2021 (December 31, 2020: $15.4 million). June 30, 2021 $ in thousands MBS Interest-Only Securities Total Principal/notional balance 8,452,735 628,908 9,081,643 Unamortized premium 259,487 — 259,487 Unamortized discount (10,176) (609,793) (619,969) Gross unrealized gains (1) 33,332 45 33,377 Gross unrealized losses (1) (21,868) (2,007) (23,875) Fair value 8,713,510 17,153 8,730,663 December 31, 2020 $ in thousands MBS Interest-Only Securities Total Principal/notional balance 7,757,491 800,426 8,557,917 Unamortized premium 391,644 — 391,644 Unamortized discount (10,067) (795,018) (805,085) Allowance for credit losses (1,768) — (1,768) Gross unrealized gains (1) 34,539 103 34,642 Gross unrealized losses (1) (4,527) (641) (5,168) Fair value 8,167,312 4,870 8,172,182 (1) Gross unrealized gains and losses includes gains (losses) recognized in net income for securities accounted for under the fair value option as well as gains (losses) for available-for-sale securities which are recognized as adjustments to other comprehensive income. Realization occurs upon sale or settlement of such securities. Further detail on the components of our total gains (losses) on investments, net for the three and six months ended June 30, 2021 and 2020 is provided below in this Note 4. The following table summarizes our MBS portfolio according to estimated weighted average life classifications as of June 30, 2021 and December 31, 2020 . $ in thousands June 30, 2021 December 31, 2020 Less than one year 264 22,112 Greater than one year and less than five years 898,499 5,303,917 Greater than or equal to five years 7,831,900 2,846,153 Total 8,730,663 8,172,182 The following tables present the estimated fair value and gross unrealized losses of our MBS by length of time that such securities have been in a continuous unrealized loss position at June 30, 2021 and December 31, 2020. June 30, 2021 Less than 12 Months 12 Months or More Total $ in thousands Fair Unrealized Number Fair Unrealized Number Fair Unrealized Number Agency RMBS: 30 year fixed-rate 4,576,277 (21,868) 38 — — — 4,576,277 (21,868) 38 Total Agency RMBS pass-through 4,576,277 (21,868) 38 — — — 4,576,277 (21,868) 38 Agency-CMO 11,640 (335) 3 — — — 11,640 (335) 3 Non-Agency RMBS 2,620 (1,648) 10 14 (24) 4 2,634 (1,672) 14 Total (1) 4,590,537 (23,851) 51 14 (24) 4 4,590,551 (23,875) 55 (1) Fair value option has been elected for all securities in an unrealized loss position. December 31, 2020 Less than 12 Months 12 Months or More Total $ in thousands Fair Unrealized Number Fair Unrealized Number Fair Unrealized Number Agency RMBS: 30 year fixed-rate 1,496,279 (4,108) 20 — — — 1,496,279 (4,108) 20 Total Agency RMBS pass-through (1) 1,496,279 (4,108) 20 — — — 1,496,279 (4,108) 20 Non-Agency CMBS (2) 27,069 (419) 1 — — — 27,069 (419) 1 Non-Agency RMBS (3) 2,681 (438) 6 1,612 (203) 7 4,293 (641) 13 Total 1,526,029 (4,965) 27 1,612 (203) 7 1,527,641 (5,168) 34 (1) Fair value option has been elected for all Agency RMBS in an unrealized loss position. (2) Unrealized losses on non-Agency CMBS are included in accumulated other comprehensive income. These losses are not reflected in an allowance for credit losses based on a comparison of discounted expected cash flows to current amortized cost basis. (3) Fair value option has been elected for all non-Agency RMBS in an unrealized loss position. As of December 31, 2020, we had recorded an allowance for credit losses of $1.8 million on a single non-Agency CMBS on our condensed consolidated balance sheet. We recorded an $830,000 and a $1.8 million decrease in the provision for credit losses on our condensed consolidated statement of operations during the three and six months ended June 30, 2021, respectively. As of June 30, 2021, we do not have an allowance for credit losses recorded on our condensed consolidated balance sheet. We did not record any provisions for credit losses during the three and six months ended June 30, 2020. During the three and six months ended June 30, 2020, we recorded impairments of $6.3 million and $85.1 million, respectively, on our condensed consolidated statement of operations because we intended to sell or more likely than not would be required to sell the securities before recovery of amortized cost basis. The following table presents a roll-forward of our allowance for credit losses. Three Months Ended June 30, Six Months Ended June 30, $ in thousands 2021 2021 Beginning allowance for credit losses (830) (1,768) Additional increases or decreases to the allowance for credit losses on securities that had an allowance recorded in a previous period 830 1,768 Ending allowance for credit losses — — The following table summarizes the components of our total gain (loss) on investments, net for the three and six months ended June 30, 2021 and 2020. Three Months Ended June 30, Six Months Ended June 30, $ in thousands 2021 2020 2021 2020 Gross realized gains on sale of investments — 253,737 201 581,865 Gross realized losses on sale of investments (118,006) (658,476) (235,054) (990,889) Impairment of investments the Company intends to sell or more likely than not will be required to sell before recovery of amortized cost basis and other impairments — (6,287) — (85,121) Net unrealized gains and losses on MBS and GSE CRT accounted for under the fair value option 189,804 105,445 (22,108) (561,427) Net unrealized gains and losses on commercial loan and loan participation interest 822 3,023 (2,276) (2,469) Realized loss on loan participation interest — (3,808) — (3,808) Total gain (loss) on investments, net 72,620 (306,366) (259,237) (1,061,849) The following tables present components of interest income recognized on our MBS and GSE CRT portfolio for the three and six months ended June 30, 2021 and 2020. GSE CRT interest income excludes coupon interest associated with embedded derivatives of $1.1 million and $5.8 million for the three and six months ended June 30, 2020, respectively, that was recorded as realized and unrealized credit derivative income (loss), net. For the three months ended June 30, 2021 $ in thousands Coupon Net (Premium Interest Agency RMBS 50,003 (9,450) 40,553 Non-Agency CMBS 1,036 845 1,881 Non-Agency RMBS 467 (274) 193 Other 7 — 7 Total 51,513 (8,879) 42,634 For the three months ended June 30, 2020 $ in thousands Coupon Net (Premium Interest Agency RMBS 1,561 (894) 667 Agency CMBS 1,827 (78) 1,749 Non-Agency CMBS 20,444 4,473 24,917 Non-Agency RMBS 1,524 (178) 1,346 GSE CRT 1,500 (536) 964 Other (15) — (15) Total 26,841 2,787 29,628 For the six months ended June 30, 2021 $ in thousands Coupon Net (Premium Interest Agency RMBS 99,558 (21,934) 77,624 Non-Agency CMBS 2,341 1,723 4,064 Non-Agency RMBS 1,091 (724) 367 Other 13 — 13 Total 103,003 (20,935) 82,068 For the six months ended June 30, 2020 $ in thousands Coupon Net (Premium Interest Agency RMBS 107,439 (21,807) 85,632 Agency CMBS 35,822 (1,744) 34,078 Non-Agency CMBS 62,662 9,531 72,193 Non-Agency RMBS 12,284 2,520 14,804 GSE CRT 10,007 (2,286) 7,721 Other 736 — 736 Total 228,950 (13,786) 215,164 |