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Accounting for Stock-Based Compensation (Tables)
6 Months Ended
Nov. 30, 2013
Accounting for Stock-Based Compensation  
Assumptions used in the Black-Scholes option pricing model to estimate the fair value of each stock option grant

 

 

 

 

Six Months Ended

 

 

 

November 30, 2013

 

Risk-free interest rate

 

1.4

%

Expected volatility of common stock

 

49.1

%

Dividend yield

 

1.2

%

Expected option term in years

 

5.2