Once vested, the delivery of the shares of restricted stock (including reinvested dividends) is deferred under our Director  Deferred Compensation Plan until the director retires, dies or becomes disabled or otherwise no longer serves as a director.  The directors may vote and are entitled to receive dividends on the underlying shares; however, any dividends on the shares of  restricted stock must be reinvested in shares of common stock and held in the deferred compensation plan until the shares of  restricted stock are delivered to the former director. In addition to automatic awards, eligible directors may be granted discretionary awards under the 1998 plan. On March 16, 2010, the Committee approved three long-term incentive performance programs, or the 2010 LTIP programs, for  certain senior executive officers. Awards under the 2010 LTIP programs take the form of LTIP units, a form of limited partnership  interest issued by the Operating Partnership. During the performance period, participants are entitled to receive on the LTIP units  awarded to them distributions equal to 10% of the regular quarterly distributions paid on a unit of the Operating Partnership.  As a result, we account for these LTIP units as participating securities under the two-class method of computing earnings per  share. Awarded LTIP units will be considered earned, in whole or in part, depending upon the extent to which the applicable total  shareholder return, or TSR, benchmarks, as defined, are achieved during the performance period and, once earned, will become  the equivalent of units after a two year service based vesting period, beginning after the end of the performance period. Awarded  LTIP units not earned are forfeited. The 2010 LTIP programs have one, two and three year performance periods, which end on December 31, 2010, 2011 and  2012, respectively. During July 2011, the Committee approved a three-year long-term incentive performance program, or the  2011-2013 LTIP program, and awarded LTIP units to certain senior executive officers. The 2011-2013 LTIP program has a three  year performance period ending on December 31, 2013. After the end of each performance period, any earned LTIP units will  then be subject to service based-vesting over a period of two years. One-half of the earned LTIP units will vest on January 1 of  each of the second and third years following the end of the applicable performance period, subject to the participant maintaining  employment with us through those dates. The 2010 LTIP program awards have an aggregate grant date fair value, adjusted for estimated forfeitures, of $7.2 million for  the one-year program, $14.8 million for the two-year program and $23.0 million for the three-year program. The 2011-2013 LTIP  program awards have an aggregate grant date fair value of $35.0 million, adjusted for estimated forfeitures. Grant date fair values  were estimated based upon the results of a Monte Carlo model, and the resulting expense will be recorded regardless of whether  the TSR benchmarks are achieved. The grant date fair values are being amortized into expense over the period from the grant date  to the date at which the awards, if any, become vested. In 2011, the Committee determined that 133,673 LTIP units were earned  under the one-year 2010 LTIP program and, pursuant to the award agreements, will vest in two equal installments in 2012 and  2013. On July 6, 2011, in connection with the execution of an employment agreement, the Committee granted David Simon, our  Chairman and CEO, a retention award in the form of a new series of 1,000,000 LTIP units. The retention award vests in one-third  increments on July 5th of 2017, 2018 and 2019, subject to continued employment. The grant date fair value of the retention award  was $120.3 million which is being recognized as expense over the eight-year vesting period on a straight-line basis. 2011 Annual Report 59 Stock Based Compensation