CASH, CASH EQUIVALENTS, AND INVESTMENTS

The following tables summarize the Company’s cash, cash equivalents, and investments’ adjusted cost, gross unrealized gains, gross unrealized losses, and fair value by significant investment category recorded as cash and cash equivalents, short-term, or long-term investments as of March 31, 2017 and 2018 (in thousands):



March 31, 2017	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Cash & Cash Equivalents		Short-term investments (due in 1 year or less)		Long-term investments (due in 1 to 3 years)
Cash	$	295,877	$	—	$	—		$	295,877	$	295,877	$	—	$	—
Level 1:
Mutual Funds	12,079		352		(32		)	12,399		—		12,399		—
US Treasury Notes	35,960		—		(68		)	35,892		—		17,560		18,332
Subtotal	48,039		352		(100		)	48,291		—		29,959		18,332
Level 2:
Government Agency Securities	54,415		20		(164		)	54,271		—		15,309		38,962
Commercial Paper	47,152		—		—			47,152		6,093		41,059		—
Corporate Bonds	141,508		64		(224		)	141,348		—		73,676		67,672
Certificates of Deposits ("CDs")	20,383		3		—			20,386		—		18,176		2,210
Subtotal	263,458		87		(388		)	263,157		6,093		148,220		108,844

Total cash, cash equivalents and investments measured at fair value	$	607,374	$	439	$	(488	)	$	607,325	$	301,970	$	178,179	$	127,176



March 31, 2018	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Fair Value		Cash & Cash Equivalents		Short-term investments (due in 1 year or less)		Long-term investments (due in 1 to 3 years)
Cash	$	308,734	$	—	$	—		$	308,734	$	308,734	$	—	$	—
Level 1:
Mutual Funds	13,336		186		(67		)	13,455		—		13,455		—
US Treasury Notes	129,373		7		(60		)	129,320		30,178		99,142		—
Money Market Funds	344		—		—			344		344		—		—
Subtotal	143,053		193		(127		)	143,119		30,522		112,597		—
Level 2:
Government Agency Securities	46,354		—		(56		)	46,298		6,978		39,320		—
Municipal Bonds	3,591		—		—			3,591		3,591		—		—
Commercial Paper	84,512		—		—			84,512		40,836		43,676		—
Corporate Bonds	54,701		—		(212		)	54,489		—		54,489		—
Certificates of Deposits ("CDs")	19,231		—		—			19,231		—		19,231		—
Subtotal	208,389		—		(268		)	208,121		51,405		156,716		—

Total cash, cash equivalents and investments measured at fair value	$	660,176	$	193	$	(395	)	$	659,974	$	390,661	$	269,313	$	—

As of March 31, 2017 and 2018, with the exception of assets related to the Company's deferred compensation plan, all of the Company's investments are classified as available-for-sale securities. The carrying value of available-for-sale securities included in cash equivalents approximates fair value because of the short maturity of those instruments. During the year ended March, 31, 2018, we sold our long-term investments and recognized a loss on sale of approximately $1.2 million. The Company did not incur any material realized or unrealized gains or losses during Fiscal Year 2017.

There were no transfers between fair value measurement levels during Fiscal Years 2017 and 2018.