Equity Plans

As of June 4, 2015, our equity plans permit us to issue an aggregate of up to 171 million shares of common stock, of which 111 million shares were available for future awards. Awards are subject to terms and conditions as determined by our Board of Directors.

Stock Options

Stock options granted and assumptions used in the Black-Scholes option valuation model were as follows:



	Quarter Ended				Nine Months Ended
	June 4, 2015		May 29, 2014		June 4, 2015		May 29, 2014
Stock options granted	—		1		8		12
Weighted-average grant-date fair value per share	$10.89		$11.35		$14.86		$9.38
Average expected life in years	5.6		5.7		5.6		4.9
Weighted-average expected volatility	42	%	52	%	45	%	48	%
Weighted-average risk-free interest rate	1.6	%	1.8	%	1.7	%	1.6	%

The expected volatilities utilized were based on implied volatilities from traded options on our stock and on our historical volatility. The expected lives of options granted were based, in part, on historical experience and on the terms and conditions of the options. The risk-free interest rates utilized were based on the U.S. Treasury yield in effect at each grant date. No dividends were assumed in estimated option values.

Restricted Stock and Restricted Stock Units ("Restricted Stock Awards")

As of June 4, 2015, there were 14 million shares of Restricted Stock Awards outstanding, of which 1 million were performance-based or market-based Restricted Stock Awards. For service-based Restricted Stock Awards, restrictions generally lapse in one-fourth increments during each year of employment after the grant date. Vesting for performance-based awards is contingent upon meeting a specified return on assets ("ROA"), as defined, over a three-year performance period and vesting for market-based Restricted Stock Awards is contingent upon achieving total shareholder return ("TSR") relative to the companies included in the S&P 500 over a three-year performance period. At the end of the performance period, the number of actual shares to be awarded varies between 0% and 200% of target amounts, depending upon the achievement level of the specified ROA or TSR. Restricted Stock Awards activity for the third quarters and first nine months of 2015 and 2014 are summarized as follows:



	Quarter Ended				Nine Months Ended
	June 4, 2015		May 29, 2014		June 4, 2015		May 29, 2014
Restricted stock awards granted	—		—		6		7
Weighted-average grant-date fair values per share	$	27.34	$	22.73	$	33.93	$	21.39

Stock-based Compensation Expense



	Quarter Ended				Nine Months Ended
	June 4, 2015		May 29, 2014		June 4, 2015		May 29, 2014
Stock-based compensation expense by caption:
Cost of goods sold	$	17	$	12	$	48	$	27
Selling, general and administrative	15		12		48		36
Research and development	11		7		31		17
Other	—		1		—		1
	$	43	$	32	$	127	$	81

Stock-based compensation expense by type of award:
Stock options	$	20	$	16	$	61	$	44
Restricted stock awards	23		16		66		37
	$	43	$	32	$	127	$	81

As of June 4, 2015, $432 million of total unrecognized compensation costs, net of estimated forfeitures, related to non-vested awards was expected to be recognized through the third quarter of 2019, resulting in a weighted-average period of 1.4 years. Stock-based compensation expense in the above presentation does not reflect any significant income tax benefits, which is consistent with our treatment of income or loss from our U.S. operations.