AMAZON COM INC | 2013 | FY | 3

The following table summarizes our restricted stock unit activity (in millions):
 
 
Number of Units
 
Weighted Average
Grant-Date
Fair Value
Outstanding as of January 1, 2011
14.0

 
$
96

Units granted
5.4

 
193

Units vested
(5.1
)
 
73

Units forfeited
(1.2
)
 
122

Outstanding as of December 31, 2011
13.1

 
143

Units granted
8.2

 
209

Units vested
(4.2
)
 
110

Units forfeited
(1.7
)
 
168

Outstanding as of December 31, 2012
15.4

 
184

Units granted
7.2

 
283

Units vested
(4.5
)
 
160

Units forfeited
(1.8
)
 
209

Outstanding as of December 31, 2013
16.3

 
$
233

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