5. Supplemental financial information

Inventory consists of the following (in thousands):

	April 30 , 201 6		January 30 , 201 6
Wafers and other purchased materials	$	12,517	$	15,440
Work-in-process		4,110		2,885
Finished goods		7,681		8,384
Total inventory	$	24,308	$	26,709

Prepaid expenses and other current assets consist of the following (in thousands):

	April 30 , 201 6		January 30 , 201 6
Prepayments for taxes	$	3,369	$	3,357
Deposits		3,210		3,200
Non-operating receivable		2,731		-
Prepayments for inventory		2,664		3,725
Prepayments for royalties		692		741
Other current assets		2,942		3,062
Total prepaid expenses and other current assets	$	15,608	$	14,085

Software, equipment and leasehold improvements consist of the following (in thousands):

	Estimated Useful Lives (years)			April 30 , 201 6			January 30 , 201 6
Software		2		$	40,697		$	40,411
Mask sets	1	-	5		14,460			14,130
Equipment	1	-	5		8,261			8,088
Office equipment and furniture		2			7,875			7,705
Leasehold improvements	1	-	6		2,115			2,089
Total					73,408			72,423
Less: Accumulated depreciation and amortization					(61,888	)		(58,337	)
Total software, equipment and leasehold improvements, net				$	11,520		$	14,086

Software, equipment and leasehold improvement depreciation and amortization expense for the three months ended April 30, 2016 and May 2, 2015 was $3.4 million and $2.9 million, respectively. We recorded an impairment charge of software related to design tools associated with discontinued products for the three months ended May 2, 2015 of less than $0.1 million which was recorded in operating expenses in the accompanying condensed consolidated statement of operations.

Accrued liabilities consist of the following (in thousands):

	April 30 , 201 6		January 30 , 201 6
License fees	$	4,135	$	5,181
Rebates		3,925		2,864
Income taxes payable, current portion		2,725		2,305
Royalties		2,156		1,469
Warranties		960		959
Deferred revenue		416		407
Other accrued liabilities		1,241		1,447
Total accrued liabilities	$	15,558	$	14,632

The following table summarizes activity related to accrued rebates (in thousands):

	Three Months Ended
	April 30, 2016			May 2, 2015

Beginning balance	$	2,864		$	9,599
Charged as a reduction of revenue		2,444			4,120
Reversal of unclaimed rebates		-			(807	)
Payments		(1,383	)		(5,770	)
Ending balance	$	3,925		$	7,142