Schedule of investments

Investments consist of the following (in thousands):


	July 27,		April 30,
	2019		2019

Short-term investments:
Held-to-maturity securities:
Municipal securities	$	7,873	$	5,332
U.S. government securities		81,689		63,205
Corporate bonds		74,072		81,950
Total held-to-maturity short-term investments	$	163,634	$	150,487
Long-term investments:
Held-to-maturity securities:
U.S. government securities		1,006		7,404
Corporate bonds		1,188		1,982
Total held-to-maturity investments		2,194		9,386
Available-for-sale securities:
Investment in limited partnership fund		2,693		—
Total available-for-sale investments		2,693		—
Total long-term investments	$	4,887	$	9,386

Schedule of amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of held-to-maturity investments

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the held-to-maturity investments as of July 27, 2019 were as follows (in thousands):


	July 27, 2019
			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value
Municipal securities	$	7,873	$	2	$	—	$	7,875
U.S. government securities		82,695		129		(11)		82,813
Corporate bonds		75,260		43		(6)		75,297
Total held-to-maturity investments	$	165,828	$	174	$	(17)	$	165,985

The amortized cost, gross unrealized gains, gross unrealized losses, and estimated fair value of the held-to-maturity investments as of April 30, 2019 were as follows (in thousands):


	April 30, 2019
			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
	Cost		Gains		Losses		Value
Municipal securities	$	5,332	$	2	$	(1)	$	5,333
U.S. government securities		70,609		78		(52)		70,635
Corporate bonds		83,932		20		(5)		83,947
Total held-to-maturity investments	$	159,873	$	100	$	(58)	$	159,915

Schedule of amortized cost and fair value by contractual maturity