notes to consolidated financial statements 2014 ( continued ) the weighted average grant-date fair value of share awards granted in the years ended may 31 , 2007 and 2006 was $ 45 and $ 36 , respectively .
the total fair value of share awards vested during the years ended may 31 , 2008 , 2007 and 2006 was $ 4.1 million , $ 1.7 million and $ 1.4 million , respectively .
we recognized compensation expenses for restricted stock of $ 5.7 million , $ 2.7 million , and $ 1.6 million in the years ended may 31 , 2008 , 2007 and 2006 .
as of may 31 , 2008 , there was $ 15.2 million of total unrecognized compensation cost related to unvested restricted stock awards that is expected to be recognized over a weighted average period of 2.9 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 $ 25 thousand or 20% ( 20 % ) of their annual compensation for the purchase of stock .
for periods prior to october 1 , 2006 , the price for shares purchased under the plan was the lower of 85% ( 85 % ) of the market value on the first day or the last day of the quarterly purchase period .
with the quarterly purchase period beginning on october 1 , 2006 , the price for shares purchased under the plan is 85% ( 85 % ) of the market value on the last day of the quarterly purchase period ( the 201cpurchase date 201d ) .
at may 31 , 2008 , 0.7 million shares had been issued under this plan , with 1.7 million shares reserved for future issuance .
the weighted average grant-date fair value of each designated share purchased under this plan was $ 6 , $ 8 and $ 8 in the years ended may 31 , 2008 , 2007 and 2006 , respectively .
for the quarterly purchases after october 1 , 2006 , the fair value of each designated share purchased under the employee stock purchase plan is based on the 15% ( 15 % ) discount on the purchase date .
for purchases prior to october 1 , 2006 , the fair value of each designated share purchased under the employee stock purchase plan was estimated on the date of grant using the black-scholes valuation model using the following weighted average assumptions: .

2007
2006
Risk-free interest rates
4.93%
3.72%
Expected volatility
37.02%
26.06%
Dividend yields
0.19%
0.34%
Expected lives
3 months
3 months

the risk-free interest rate is based on the yield of a zero coupon united states treasury security with a maturity equal to the expected life of the option from the date of the grant .
our assumption on expected volatility is based on our historical volatility .
the dividend yield assumption is calculated using our average stock price over the preceding year and the annualized amount of our current quarterly dividend .
since the purchase price for shares under the plan is based on the market value on the first day or last day of the quarterly purchase period , we use an expected life of three months to determine the fair value of each designated share. .

Question: Analyse this data from a financial earnings document. what is the percentage change in the weighted average grant-date fair value of share awards from 2006 to 2007?
Choices:
0.25
-0.25
1.36
0.2
24.31
Correct choice index: 0