The following tables reflect the components of significant balance sheet accounts as of December 29, 2018 and September 29, 2018:



	As of
(in thousands)	December 29, 2018			September 29, 2018

Short term investments, available-for-sale⁽¹⁾	$	355,000		$	293,000

Inventories, net:
Raw materials and supplies	$	63,633		$	63,894
Work in process	36,204			37,829
Finished goods	36,711			40,357
	136,548			142,080
Inventory reserves	(26,817		)	(26,889		)
	$	109,731		$	115,191
Property, plant and equipment, net:
Land	$	2,182		$	2,182
Buildings and building improvements	52,323			52,449
Leasehold improvements	12,868			12,728
Data processing equipment and software	36,105			35,469
Machinery, equipment, furniture and fixtures	70,066			68,666
Construction in progress	8,492			6,940
	182,036			178,434
Accumulated depreciation	(104,716		)	(102,367		)
	$	77,320		$	76,067
Accrued expenses and other current liabilities:
Wages and benefits	$	19,391		$	44,505
Accrued customer obligations ⁽²⁾	33,491			34,918
Dividend payable	8,055			8,057
Commissions and professional fees	3,981			5,549
Deferred rent	1,820			1,847
Severance	717			1,415
Other	8,450			9,687
	$	75,905		$	105,978


(1)	All short-term investments were classified as available-for-sale and were measured at fair value based on level one measurement, or quoted market prices, as defined by ASC 820. The Company did not recognize any realized gains or losses on the sale of investments during the three months ended December 29, 2018 and December 30, 2017.


(2)	Represents customer advance payments, customer credit program, accrued warranty expense and accrued retrofit obligations.