|                                         |   | Year Ended December 31, |   |
|----------------------------------------------|--------|-------------------------|--------|
|                                         |   | 2014                    |   |   | 2013 |   |   | 2012 |   |   | 2011 |   |   | 2010 |   |
| Earnings:                                    |   |                    |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Net income                                   |   | $                       | 1,433  |   |   | $ | 866 |   |   | $ | 811 |   |   | $ | 845 |   |   | $ | 1,121 |   |
| Income tax provision                         |   |                    | 384    |   |   |   | 326 |   |   |   | 298 |   |   |   | 480 |   |   |   | 574 |   |
| Fixed charges                                |   |                    | 1,176  |   |   |   | 971 |   |   |   | 891 |   |   |   | 880 |   |   |   | 799 |   |
| Total earnings                               |   | $                       | 2,993  |   |   | $ | 2,163 |   |   | $ | 2,000 |   |   | $ | 2,205 |   |   | $ | 2,494 |   |
| Fixed charges:                               |   |                    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Interest on short-term borrowings and        |   |                    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| long-term debt, net                          |   | $                       | 1,125  |   |   | $ | 917 |   |   | $ | 834 |   |   | $ | 824 |   |   | $ | 731 |   |
| Interest on capital leases                   |   |                    | 6      |   |   |   | 7 |   |   |   | 9 |   |   |   | 16 |   |   |   | 18 |   |
| AFUDC debt                                   |   |                    | 45     |   |   |   | 47 |   |   |   | 48 |   |   |   | 40 |   |   |   | 50 |   |
| Total fixed charges                          |   | $                       | 1,176  |   |   | $ | 971 |   |   | $ | 891 |   |   | $ | 880 |   |   | $ | 799 |   |
| Preferred stock dividends:                   |   |                    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Tax deductible dividends                     |   | $                       | 9      |   |   | $ | 9 |   |   | $ | 9 |   |   | $ | 9 |   |   | $ | 9 |   |
| Pre-tax earnings required to cover non-tax   |   |                    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| deductible preferred stock dividend          |   |                    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| requirements                                 |   |                    | 6      |   |   |   | 7 |   |   |   | 7 |   |   |   | 8 |   |   |   | 7 |   |
| Total preferred stock dividends              |   |                    | 15     |   |   |   | 16 |   |   |   | 16 |   |   |   | 17 |   |   |   | 16 |   |
| Total combined fixed charges and             |   |                    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| preferred stock dividends                    |   | $                       | 1,191  |   |   | $ | 987 |   |   | $ | 907 |   |   | $ | 897 |   |   | $ | 815 |   |
| Ratios of earnings to combined fixed charges |   |                    |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| and preferred stock dividends                |   |                    | 2.51   |   |   |   | 2.19 |   |   |   | 2.21 |   |   |   | 2.46 |   |   |   | 3.06 |   |