25. Share-Based Compensation

        We maintain a long-term incentive plan (the Plan) for key team members and non-employee members of our Board of Directors. Our long-term incentive plan allows us to grant equity-based compensation awards, including stock options, stock appreciation rights, performance share units, restricted stock units, restricted stock awards or a combination of awards (collectively, share-based awards). The number of unissued common shares reserved for future grants under the Plan was 32.5 million at January 28, 2012 and 17.5 million at January 29, 2011.

        Total share-based compensation expense recognized in the Consolidated Statements of Operations was $90 million, $109 million and $103 million in 2011, 2010 and 2009, respectively. The related income tax benefit was $35 million, $43 million and $40 million in 2011, 2010 and 2009, respectively.

Stock Options

        We grant nonqualified stock options to certain team members under the Plan that generally vest and become exercisable annually in equal amounts over a four-year period and expire 10 years after the grant date. We also grant options with a ten-year term to the non-employee members of our Board of Directors which vest immediately, but are not exercisable until one year after the grant date.

        We use a Black-Scholes valuation model to estimate the fair value of the options at grant date based on the assumptions noted in the following table. Volatility represents an average of market estimates for implied volatility of Target common stock. The expected life is estimated based on an analysis of options already exercised and any foreseeable trends or changes in recipients' behavior. The risk-free interest rate is an interpolation of the relevant U.S. Treasury security maturities as of each applicable grant date.

        Compensation expense associated with stock options is recognized on a straight-line basis over the shorter of the vesting period or the minimum required service period. At January 28, 2012, there was $109 million of total unrecognized compensation expense related to nonvested stock options, which is expected to be recognized over a weighted average period of 1.4 years. The weighted average remaining life of currently exercisable options is 5.0 years, and the weighted average remaining life of all outstanding options is 6.6 years. The total fair value of options vested was $75 million, $87 million and $85 million in 2011, 2010 and 2009, respectively.

Performance Share Units

        We have issued performance share units to certain team members annually since January 2003. These units represent shares potentially issuable in the future. Issuance is based upon our performance relative to a retail peer group over a three-year performance period on two measures: domestic market share change and EPS growth. The fair value of performance share units is calculated based on the stock price on the date of grant. The weighted average grant date fair value for performance share units was $48.63 in 2011, $52.62 in 2010 and $27.18 in 2009.

        Compensation expense associated with unvested performance share units is recognized on a straight-line basis over the shorter of the vesting period or the minimum required service period. The expense recognized each period is dependent upon our estimate of the number of shares that will ultimately be issued. Future compensation expense for currently unvested awards could reach a maximum of $19 million assuming payout of all unvested awards. The unrecognized expense is expected to be recognized over a weighted average period of 0.8 years. The fair value of performance share units vested and converted was not significant in 2011, 2010 and 2009.

Restricted Stock

        We issue restricted stock units and restricted stock awards (collectively restricted stock) to certain team members with three-year cliff vesting from the date of grant. We also regularly issue restricted stock units to our Board of Directors, which vest quarterly over a one-year period and are settled in shares of Target common stock upon departure from the Board. Restricted stock units represent shares potentially issuable in the future whereas restricted stock awards represent shares issued upon grant that are restricted. The fair value for restricted stock units and restricted stock awards is calculated based on the stock price on the date of grant. The weighted average grant date fair value for restricted stock was $49.42 in 2011, $55.17 in 2010 and $49.41 in 2009.

        Compensation expense associated with unvested restricted stock is recognized on a straight-line basis over the shorter of the vesting period or the minimum required service period. The expense recognized each period is dependent upon our estimate of the number of shares that will ultimately be issued. At January 28, 2012, there was $44 million of total unrecognized compensation expense related to restricted stock, which is expected to be recognized over a weighted average period of 1.3 years. The fair value of restricted stock vested and converted was $9 million in 2011, $3 million in 2010 and $12 million in 2009.