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Equity Plans | 6 Months Ended
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Mar. 01, 2012
Notes to Financial Statements [Abstract] |
Equity Plans | Equity Plans As of March 1, 2012, we had an aggregate of 186.5 million shares of common stock reserved for the issuance of stock options and restricted stock awards, of which 108.4 million shares were subject to outstanding awards and 78.1 million shares were available for future awards. Awards are subject to terms and conditions as determined by our Board of Directors. Stock Options We granted 14.5 million and 20.4 million stock options during the second quarter and first six months of 2012, respectively, with weighted-average grant-date fair values per share of $3.25 and $3.16, respectively. We granted 10.8 million and 14.9 million stock options during the second quarter and first six months of 2011, respectively, with weighted-average grant-date fair values per share of $4.71 and $4.46, respectively. The fair values of option awards were estimated as of the dates of grant using the Black-Scholes option valuation model. The Black-Scholes model requires the input of assumptions, including the expected stock price volatility and estimated option life. The expected volatilities utilized were based on implied volatilities from traded options on our stock and on historical volatility. Since 2009, the expected lives of options granted were based, in part, on historical experience and on the terms and conditions of the options. Prior to 2009, the expected lives of options granted were based on the simplified method provided by the Securities and Exchange Commission. The risk-free interest rates utilized were based on the U.S. Treasury yield in effect at the time of the grant. No dividends were assumed in estimated option values. Assumptions used in the Black-Scholes model are presented below:
|  | Quarter Ended |  | Six Months Ended
|  | March 1, 2012 |  | March 3, 2011 |  | March 1, 2012 |  | March 3, 2011
Average expected life in years |  | 5.1 |  |  | 5.0 |  |  | 5.1 |  |  | 5.1 |
Weighted-average expected volatility |  | 66 | % |  | 55 | % |  | 66 | % |  | 56 | %
Weighted-average risk-free interest rate |  | 0.9 | % |  | 2.1 | % |  | 1.0 | % |  | 1.8 | %
Restricted Stock and Restricted Stock Units ("Restricted Stock Awards") As of March 1, 2012, there were 10.4 million shares of Restricted Stock Awards outstanding, of which 2.4 million were performance-based Restricted Stock Awards. For service-based Restricted Stock Awards, restrictions generally lapse either in one-fourth or one-third increments during each year of employment after the grant date. For performance-based Restricted Stock Awards, vesting is contingent upon meeting certain performance goals. Restricted Stock Awards granted for the second quarters and first six months of 2012 and 2011 were as follows:
|  | Quarter Ended |  | Six Months Ended
|  | March 1, 2012 |  | March 3, 2011 |  | March 1, 2012 |  | March 3, 2011
Service-based awards |  | 2.0 |  |  | 3.1 |  |  | 3.8 |  |  | 4.3 |
Performance-based awards |  | — |  |  | — |  |  | 1.9 |  |  | 1.2 |
Weighted-average grant-date fair values per share |  | $ | 5.84 |  |  | $ | 9.62 |  |  | $ | 5.40 |  |  | $ | 8.74 |
Stock-based Compensation Expense Total compensation costs for our equity plans were as follows:
|  | Quarter Ended |  | Six Months Ended
|  | March 1, 2012 |  | March 3, 2011 |  | March 1, 2012 |  | March 3, 2011
Stock-based compensation expense by caption: |  |  |  |  |  |  |  |
Cost of goods sold |  | $ | 7 |  |  | $ | 6 |  |  | $ | 12 |  |  | $ | 10 |
Selling, general and administrative |  | 18 |  |  | 9 |  |  | 29 |  |  | 20 |
Research and development |  | 5 |  |  | 4 |  |  | 9 |  |  | 8 |
|  | $ | 30 |  |  | $ | 19 |  |  | $ | 50 |  |  | $ | 38 |
Stock-based compensation expense by type of award: |  |  |  |  |  |  |  |  |  |
Stock options |  | $ | 19 |  |  | $ | 11 |  |  | $ | 31 |  |  | $ | 21 |
Restricted stock awards |  | 11 |  |  | 8 |  |  | 19 |  |  | 17 |
|  | $ | 30 |  |  | $ | 19 |  |  | $ | 50 |  |  | $ | 38 |
Selling, general and administrative expense for the second quarter of 2012 included $9 million from the acceleration and extension of vesting of our former Chief Executive Officer's restricted stock and stock options upon his death, pursuant to the terms of our stock plans and his severance agreement. As of March 1, 2012, $173 million of total unrecognized compensation costs, net of estimated forfeitures, related to non-vested awards was expected to be recognized through the second quarter of 2016, 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. (See "Income Taxes" note.)

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