. the price for shares purchased under the plan is 85% ( 85 % ) of the market value on the last day of the quarterly purchase period . as of may 31 , 2013 , 1.0 million shares had been issued under this plan , with 1.4 million shares reserved for future issuance . we recognized compensation expense for the plan of $ 0.5 million in the years ended may 31 , 2013 , 2012 and 2011