Earnings per Share

6 Months Ended

Jun. 30, 2019

EARNINGS PER SHARE

We compute basic earnings per share by dividing net income attributable to MPC less income allocated to participating securities by the weighted average number of shares of common stock outstanding. Since MPC grants certain incentive compensation awards to employees and non-employee directors that are considered to be participating securities, we have calculated our earnings per share using the two-class method. Diluted income per share assumes exercise of certain stock-based compensation awards, provided the effect is not anti-dilutive.



	Three Months Ended June 30,				Six Months Ended June 30,
(In millions, except per share data)	2019		2018		2019		2018
Basic earnings per share:
Allocation of earnings:
Net income attributable to MPC	$	1,106	$	1,055	$	1,099	$	1,092
Income allocated to participating securities	—		1		1		1
Income available to common stockholders – basic	$	1,106	$	1,054	$	1,098	$	1,091
Weighted average common shares outstanding	662		459		667		467
Basic earnings per share	$	1.67	$	2.30	$	1.65	$	2.34
Diluted earnings per share:
Allocation of earnings:
Net income attributable to MPC	$	1,106	$	1,055	$	1,099	$	1,092
Income allocated to participating securities	—		1		1		1
Income available to common stockholders – diluted	$	1,106	$	1,054	$	1,098	$	1,091
Weighted average common shares outstanding	662		459		667		467
Effect of dilutive securities	4		5		5		5
Weighted average common shares, including dilutive effect	666		464		672		472
Diluted earnings per share	$	1.66	$	2.27	$	1.63	$	2.31

The following table summarizes the shares that were anti-dilutive and, therefore, were excluded from the diluted share calculation.



	Three Months Ended June 30,		Six Months Ended June 30,
(In millions)	2019	2018	2019	2018
Shares issuable under stock-based compensation plans	4	1	3	1