| Year Ended December 31, | Three months ended March 31, | ||||||||||||||||||||||||
| Earnings: | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | |||||||||||||||||||
| Income from continuing operations | |||||||||||||||||||||||||
| before tax and noncontrolling interest | $ | 1,279 | $ | 2,039 | $ | 1,618 | $ | 1,755 | $ | 1,106 | $ | 310 | |||||||||||||
| Less: Income from equity investees | — | — | — | — | — | — | |||||||||||||||||||
| Income from continuing operations before income from equity investees, tax and noncontrolling interest | 1,279 | 2,039 | 1,618 | 1,755 | 1,106 | 310 | |||||||||||||||||||
| Add: | |||||||||||||||||||||||||
| Fixed charges (see below) | 580 | 581 | 577 | 581 | 630 | 167 | |||||||||||||||||||
| Amortization of capitalized interest | 3 | 1 | — | — | — | — | |||||||||||||||||||
| Distributed income of equity investees | — | — | — | — | — | — | |||||||||||||||||||
| Loss of equity investees for which charges arising from guarantees are included in fixed charges | — | — | — | — | — | — | |||||||||||||||||||
| Subtract: | |||||||||||||||||||||||||
| Interest capitalized | (6 | ) | (2 | ) | (1 | ) | (1 | ) | (1 | ) | — | ||||||||||||||
| Preference security dividend requirements of consolidated subsidiaries - pre-tax basis | — | — | — | — | — | — | |||||||||||||||||||
| Noncontrolling interest of subsidiaries that have not incurred | |||||||||||||||||||||||||
| fixed charges - pre-tax basis | — | — | — | — | — | — | |||||||||||||||||||
| Earnings as adjusted | $ | 1,856 | $ | 2,619 | $ | 2,194 | $ | 2,335 | $ | 1,735 | $ | 477 | |||||||||||||
| Fixed Charges: | |||||||||||||||||||||||||
| Interest expenses - net of capitalized interest and AFUDC | $ | 523 | $ | 533 | $ | 526 | $ | 541 | $ | 589 | $ | 155 | |||||||||||||
| Add: AFUDC | 31 | 25 | 31 | 23 | 28 | 10 | |||||||||||||||||||
| Interest expenses - net of capitalized interest | 554 | 558 | 557 | 564 | 617 | 165 | |||||||||||||||||||
Interest capitalized (1) | 6 | 2 | 1 | 1 | 1 | — | |||||||||||||||||||
Interest portion of rental expense (2) | 20 | 21 | 19 | 16 | 12 | 2 | |||||||||||||||||||
| Total fixed charges | $ | 580 | $ | 581 | $ | 577 | $ | 581 | $ | 630 | $ | 167 | |||||||||||||
| Ratio | 3.20 | 4.51 | 3.80 | 4.02 | 2.75 | 2.86 | |||||||||||||||||||
(2) | Rentals include the interest factor relating to certain significant rentals plus one-third of all remaining annual rentals, except for amounts allocated to power purchase contracts that are classified as operating leases. |
