For the years ended December 31, 2013, 2012 and 2011, the number of shares repurchased pursuant to trading plans under Rule 10b5-1 of the Securities Exchange Act of 1934, as amended, and their cost are as follows (millions):
| Total Number of Shares Repurchased | Total Cost of Shares Repurchased | ||||||
| 2013 | 60 | $ | 3,700 | ||||
| 2012 | 80 | $ | 3,302 | ||||
| 2011 | 136 | $ | 4,618 | ||||