

	January 26, 2020
	Amortized Cost		Unrealized Gain		Unrealized Loss		Estimated Fair Value		Reported as
	Amortized Cost		Unrealized Gain		Unrealized Loss		Estimated Fair Value		Cash Equivalents		Marketable Securities
	(In millions)
Money market funds	$	7,507	$	—	$	—	$	7,507	$	7,507	$	—
Debt securities issued by the United States Treasury	1,358		—		—		1,358		1,358		—
Debt securities issued by United States government agencies	1,096		—		—		1,096		1,096		—
Corporate debt securities	592		—		—		592		592		—
Foreign government bonds	200		—		—		200		200		—
Certificates of deposit	27		—		—		27		27		—
Asset-backed securities	1		—		—		1		—		1
Total	$	10,781	$	—	$	—	$	10,781	$	10,780	$	1



	January 27, 2019
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value		Reported as
	Amortized Cost		Unrealized Gain		Unrealized Loss			Estimated Fair Value		Cash Equivalents		Marketable Securities
	(In millions)
Corporate debt securities	$	2,626	$	—	$	(6	)	$	2,620	$	25	$	2,595
Debt securities issued by United States government agencies	2,284		—		(4		)	2,280		—		2,280
Debt securities issued by the United States Treasury	1,493		—		(1		)	1,492		176		1,316
Money market funds	483		—		—			483		483		—
Foreign government bonds	209		—		—			209		—		209
Asset-backed securities	152		—		(1		)	151		—		151
Mortgage backed securities issued by United States government-sponsored enterprises	88		1		—			89		—		89
Total	$	7,335	$	1	$	(12	)	$	7,324	$	684	$	6,640

The amortized cost and estimated fair value of cash equivalents and marketable securities as of January 26, 2020 and January 27, 2019 are shown below by contractual maturity.



	January 26, 2020				January 27, 2019
	Amortized Cost		Estimated Fair Value		Amortized Cost		Estimated Fair Value
	(In millions)
Less than one year	$	10,781	$	10,781	$	5,042	$	5,034
Due in 1 - 5 years	—		—		2,271		2,268
Mortgage-backed securities issued by United States government-sponsored enterprises not due at a single maturity date	—		—		22		22
Total	$	10,781	$	10,781	$	7,335	$	7,324

The unrealized losses as of January 26, 2020, aggregated by investment category and length of time that individual securities have been in a continuous loss position is not significant.