UNITEDHEALTH GROUP INC | 2013 | FY | 3

The principal assumptions the Company used in calculating grant-date fair value for stock options and SARs were as follows:
 
 
2013
 
2012
 
2011
Risk-free interest rate
 
1.0% - 1.6%
 
0.7% - 0.9%
 
0.9% - 2.3%
Expected volatility
 
41.0% - 43.0%
 
43.2% - 44.0%
 
44.3% - 45.1%
Expected dividend yield
 
1.4% - 1.6%
 
1.2% - 1.7%
 
1.0% - 1.4%
Forfeiture rate
 
5.0%
 
5.0%
 
5.0%
Expected life in years
 
5.3
 
5.3 - 5.6
 
4.9 - 5.0

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