Stock-Based Compensation (Tables)

The major components of stock-based compensation expense are as follows (amounts in thousands):



	Fiscal Year Ended March 31, 2016						Fiscal Year Ended March 31, 2015						Fiscal Year Ended March 31, 2014
	Stock Options		Restricted Stock		LTIPs		Stock Options		Restricted Stock		LTIPs		Stock Options		Restricted Stock		LTIPs
Cost of sales	$	81	$	617	$	720	$	233	$	269	$	1,075	$	421	$	62	$	523
Selling, general and administrative expenses	78		1,352		1,732		306		787		1,547		413		580		712
Research and development	4		23		167		13		3		279		5		—		193
	$	163	$	1,992	$	2,619	$	552	$	1,059	$	2,901	$	839	$	642	$	1,428

Employee stock option activity for fiscal year 2016 is as follows:



	Options (in thousands)		Weighted- Average Exercise Price
Outstanding at March 31, 2015	1,451		$	8.49
Granted	—		—
Exercised	—		—
Forfeited	(20	)	5.45
Expired	(177	)	14.96
Outstanding at March 31, 2016	1,254		7.63
Exercisable at March 31, 2016	1,170		$	7.76
Remaining weighted average contractual life of options exercisable (years)			4.9
Remaining weighted average contractual life of options outstanding (years)			5.1

The following table summarizes the weighted average assumptions used in the Black-Scholes valuation model to value stock option grants:



	Fiscal Years Ended March 31,
	2016	2015	2014
Assumptions:
Expected volatility (1)	N/A	N/A	59.8	%
Risk-free interest rate (2)	N/A	N/A	1.0	%
Expected option lives in years (3)	N/A	N/A	4.0
Dividend yield (4)	N/A	N/A	—

Restricted stock unit activity for fiscal year 2016 is as follows (amounts in thousands except fair value):



	Shares		Weighted- average Fair Value on Grant Date
Non-vested restricted stock at March 31, 2015	1,000		$	4.57
Granted	748		2.72
Vested	(304	)	4.98
Forfeited	(14	)	5.31
Non-vested restricted stock at March 31, 2016	1,430		$	3.51