NIKE INC | 2013 | FY | 3

The weighted average assumptions used to estimate these fair values are as follows:
 
 
Year Ended May 31,
  
 
2013
 
2012
 
2011
Dividend yield
 
1.5
%
 
1.4
%
 
1.6
%
Expected volatility
 
35.0
%
 
29.5
%
 
31.5
%
Weighted average expected life (in years)
 
5.3

 
5.0

 
5.0

Risk-free interest rate
 
0.6
%
 
1.4
%
 
1.7
%

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