{"pre_text": ["grants of restricted awards are subject to forfeiture if a grantee , among other conditions , leaves our employment prior to expiration of the restricted period .", "new grants of restricted awards generally vest one year after the date of grant in 25% ( 25 % ) increments over a four year period , with the exception of tsrs which vest after a three year period .", "the following table summarizes the changes in non-vested restricted stock awards for the years ended may 31 , 2013 and 2012 ( share awards in thousands ) : shares weighted average grant-date fair value ."], "post_text": ["the total fair value of share awards vested during the years ended may 31 , 2013 , 2012 and 2011 was $ 13.6 million , $ 12.9 million and $ 10.8 million , respectively .", "we recognized compensation expense for restricted stock of $ 16.2 million , $ 13.6 million , and $ 12.5 million in the years ended may 31 , 2013 , 2012 and 2011 , respectively .", "as of may 31 , 2013 , there was $ 33.5 million of total unrecognized compensation cost related to unvested restricted stock awards that is expected to be recognized over a weighted average period of 2.5 years .", "employee stock purchase plan we have an employee stock purchase plan under which the sale of 2.4 million shares of our common stock has been authorized .", "employees may designate up to the lesser of $ 25000 or 20% ( 20 % ) of their annual compensation for the purchase of stock .", "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 .", "the weighted average grant-date fair value of each designated share purchased under this plan during the years ended may 31 , 2013 , 2012 and 2011 was $ 6 , $ 7 and $ 6 , respectively , which represents the fair value of the 15% ( 15 % ) discount .", "stock options stock options are granted at 100% ( 100 % ) of fair market value on the date of grant and have 10-year terms .", "stock options granted vest one year after the date of grant in 25% ( 25 % ) increments over a four year period .", "the plans provide for accelerated vesting under certain conditions .", "there were no options granted under the plans during the years ended may 31 , 2013 and may 31 , 2012. ."], "table": [["", "shares", "weighted averagegrant-datefair value"], ["non-vested at may 31 2011", "869", "$ 40"], ["granted", "472", "48"], ["vested", "-321 ( 321 )", "40"], ["forfeited", "-79 ( 79 )", "43"], ["non-vested at may 31 2012", "941", "44"], ["granted", "561", "44"], ["vested", "-315 ( 315 )", "43"], ["forfeited", "-91 ( 91 )", "44"], ["non-vested at may 31 2013", "1096", "$ 44"]], "table_ori": [["", "Shares", "Weighted AverageGrant-DateFair Value"], ["Non-vested at May 31, 2011", "869", "$40"], ["Granted", "472", "48"], ["Vested", "(321)", "40"], ["Forfeited", "(79)", "43"], ["Non-vested at May 31, 2012", "941", "44"], ["Granted", "561", "44"], ["Vested", "(315)", "43"], ["Forfeited", "(91)", "44"], ["Non-vested at May 31, 2013", "1,096", "$44"]]}

Question: what is the net change of the total fair value balance of non-vested shares during 2013?
Evidence:
table_5: the non-vested at may 31 2012 of shares is 941 ; the non-vested at may 31 2012 of weighted averagegrant-datefair value is 44 ;
table_9: the non-vested at may 31 2013 of shares is 1096 ; the non-vested at may 31 2013 of weighted averagegrant-datefair value is $ 44 ;
Program: multiply(941, 44), multiply(1096, 44), subtract(#1, #0)
Answer:
str_answer: 6820
exe_answer: 6820