Equity Plans

As of March 3, 2016, our equity plans permit us to issue an aggregate of up to 153 million shares of common stock, of which 87 million shares were available for future awards.

Stock Options

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



	Quarter ended						Six months ended
	March 3, 2016			March 5, 2015			March 3, 2016			March 5, 2015
Stock options granted	5			7			7			8
Weighted-average grant-date fair value per share	$	6.59		$	15.34		$	7.01		$	14.96
Average expected life in years	5.5			5.6			5.5			5.6
Weighted-average expected volatility	47		%	44		%	47		%	45		%
Weighted-average risk-free interest rate	1.7		%	1.7		%	1.7		%	1.7		%

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 March 3, 2016, there were 19 million shares of Restricted Stock Awards outstanding, of which 2 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 was as follows:



	Quarter ended				Six months ended
	March 3, 2016		March 5, 2015		March 3, 2016		March 5, 2015
Restricted stock awards granted	6		4		9		6
Weighted-average grant-date fair value per share	$	14.71	$	35.85	$	15.84	$	34.33

Stock-based Compensation Expense

As of March 3, 2016, $458 million of total unrecognized compensation costs for unvested awards, net of estimated forfeitures, was expected to be recognized through the second quarter of 2020, resulting in a weighted-average period of 1.3 years. Stock-based compensation expense in the below presentation does not reflect any significant income tax benefits, which is consistent with our treatment of income or loss from our U.S. operations:



	Quarter ended				Six months ended
	March 3, 2016		March 5, 2015		March 3, 2016		March 5, 2015
Stock-based compensation expense by caption
Cost of goods sold	$	21	$	19	$	38	$	31
Selling, general, and administrative	19		18		37		33
Research and development	15		12		26		20
	$	55	$	49	$	101	$	84

Stock-based compensation expense by type of award
Stock options	$	22	$	23	$	42	$	41
Restricted stock awards	33		26		59		43
	$	55	$	49	$	101	$	84