Trading securities are recorded at fair value with subsequent changes in fair value recorded as “Fair value gains (losses), net” in our condensed consolidated statements of operations and comprehensive income. The following table displays our investments in trading securities.


	As of
	June 30, 2021			December 31, 2020
	(Dollars in millions)
Mortgage-related securities:
Fannie Mae		$	1,836		$	2,404
Other agency(1)		3,333			3,451
Private-label and other mortgage securities		152			158
Total mortgage-related securities (includes $689 million and $793 million, respectively, related to consolidated trusts)		5,321			6,013
Non-mortgage-related securities:
U.S. Treasury securities		89,707			130,456
Other securities		73			73
Total non-mortgage-related securities		89,780			130,529
Total trading securities		$	95,101		$	136,542


	For the Three Months Ended June 30,				For the Six Months Ended June 30,

	2021		2020			2021		2020
	(Dollars in millions)
Net trading gains (losses)	$	161	$	135		$	(597)	$	782
Net trading gains (losses) recognized in the period related to securities still held at period end	156		70			(586)		525

We record AFS securities at fair value with unrealized gains and losses, recorded net of tax, as a component of “Other comprehensive income (loss)” and we recognize realized gains and losses from the sale of AFS securities in “Investment gains (losses), net” in our condensed consolidated statements of operations and comprehensive income. We define the amortized cost basis of our AFS securities as unpaid principal balance, net of unamortized premiums and discounts, and other cost basis adjustments. We record an allowance for credit losses for AFS securities that reflects the impairment for credit losses, which are limited to the amount that fair value is less than the amortized cost. Impairment due to non-credit losses are recorded as unrealized losses within other comprehensive income.

The following tables display the amortized cost, allowance for credit losses, gross unrealized gains and losses in accumulated other comprehensive income (loss) (“AOCI”), and fair value by major security type for AFS securities.


	As of June 30, 2021
	Total Amortized Cost(1)			Allowance for Credit Losses		Gross Unrealized Gains in AOCI		Gross Unrealized Losses in AOCI			Total Fair Value(1)
	(Dollars in millions)
Fannie Mae		$	550	$	—	$	20		$	(7)	$	563
Other agency(2)		14		—		1			—		15
Alt-A and subprime private-label securities		4		—		1			—		5

Mortgage revenue bonds		169		(3)		6			—		172
Other mortgage-related securities		195		—		5			—		200
Total		$	932	$	(3)	$	33		$	(7)	$	955


	As of December 31, 2020
	Total Amortized Cost(1)			Allowance for Credit Losses			Gross Unrealized Gains in AOCI			Gross Unrealized Losses in AOCI			Total Fair Value(1)
	(Dollars in millions)
Fannie Mae		$	1,094		$	—		$	86		$	(12)	$	1,168
Other agency(2)		59			—			6			—		65
Alt-A and subprime private-label securities		4			—			2			—		6
Mortgage revenue bonds		211			(3)			8			—		216
Other mortgage-related securities		238			—			4			—		242
Total		$	1,606		$	(3)		$	106		$	(12)	$	1,697

(1)We exclude from amortized cost and fair value accrued interest of $3 million and $6 million as of June 30, 2021 and December 31, 2020, respectively, which we record in “Other assets” in our condensed consolidated balance sheets.

Our Fannie Mae and other agency AFS securities consist of securities issued by us, Freddie Mac, or Ginnie Mae. The principal and interest on these securities are guaranteed by the issuing agency. We believe that the guaranty provided by the issuing agency, the support provided to the agencies by the U.S. government, the importance of the agencies to the liquidity and stability in the secondary mortgage market, and the long history of zero credit losses on agency mortgage-related securities are all indicators that there are currently no credit losses on these securities, even if the security is in an unrealized loss position. In addition, we generally hold these securities that are in an unrealized loss position to recovery. As a result, unless we intend to sell the security, we do not recognize an allowance for credit losses on agency mortgage-related securities.

As of June 30, 2021, substantially all of our non-agency mortgage-related securities were in an unrealized gain position. As a result, we have not recognized an allowance for credit losses on these securities.

The following tables display additional information regarding gross unrealized losses and fair value by major security type for AFS securities in an unrealized loss position, excluding allowance for credit losses.


	As of
	June 30, 2021										December 31, 2020
	Less Than 12 Consecutive Months					12 Consecutive Months or Longer					Less Than 12 Consecutive Months					12 Consecutive Months or Longer
	Gross Unrealized Losses in AOCI			Fair Value		Gross Unrealized Losses in AOCI			Fair Value		Gross Unrealized Losses in AOCI			Fair Value		Gross Unrealized Losses in AOCI			Fair Value
	(Dollars in millions)
Fannie Mae		$	—	$	—		$	(7)	$	129		$	(1)	$	40		$	(11)	$	94


	For the Three Months Ended June 30,				For the Six Months Ended June 30,

	2021		2020		2021		2020
	(Dollars in millions)
Gross realized gains	$	46	$	9	$	59	$	30

Total proceeds (excludes initial sale of securities from new portfolio securitizations)	467		71		582		121


	As of
	June 30, 2021		December 31, 2020
	(Dollars in millions)
Net unrealized gains on AFS securities for which we have not recorded an allowance for credit losses	$	20	$	74

Other	37		42
Accumulated other comprehensive income	$	57	$	116

The following table displays the amortized cost and fair value of our AFS securities by major security type and remaining contractual maturity, assuming no principal prepayments. The contractual maturity of mortgage-backed securities is not a reliable indicator of their expected life because borrowers generally have the right to prepay their obligations at any time.


	As of June 30, 2021
	Total Carrying Amount(1)			Total Fair Value		One Year or Less					After One Year Through Five Years					After Five Years Through Ten Years					After Ten Years
						Net Carrying Amount(1)			Fair Value		Net Carrying Amount(1)			Fair Value		Net Carrying Amount(1)			Fair Value		Net Carrying Amount(1)			Fair Value
	(Dollars in millions)
Fannie Mae		$	550	$	563		$	—	$	—		$	3	$	3		$	12	$	14		$	535	$	546
Other agency		14		15			—		—			—		—			1		1			13		14
Alt-A and subprime private-label securities		4		5			—		—			—		—			2		2			2		3

Mortgage revenue bonds		166		172			1		1			23		24			19		19			123		128
Other mortgage-related securities		195		200			—		—			—		—			4		5			191		195
Total		$	929	$	955		$	1	$	1		$	26	$	27		$	38	$	41		$	864	$	886