Earnings Per Share

Basic and diluted earnings per share are computed using the two-class method, which is an earnings allocation method that determines earnings per share for common shares and participating securities. The undistributed earnings are allocated between common shares and participating securities as if all earnings had been distributed during the period. Participating securities and common shares have equal rights to undistributed earnings.

Basic earnings per share is calculated by taking net earnings, less earnings available to participating securities, divided by the basic weighted average common shares outstanding.

Diluted earnings per share is calculated by taking net earnings, less earnings available to participating securities, divided by the diluted weighted average common shares outstanding.

The elements used in the computation of basic and diluted earnings per share were as follows:



(In millions - except per share amounts)	Three months ended March 31
	2018		2017
Net earnings		$2,477		$1,579
Less: earnings available to participating securities	3		2
Net earnings available to common shareholders		$2,474		$1,577
Basic
Basic weighted average shares outstanding	590.8		614.4
Less: participating securities	0.7		0.8
Basic weighted average common shares outstanding	590.1		613.6
Diluted
Basic weighted average shares outstanding	590.8		614.4
Dilutive potential common shares⁽¹⁾	6.4		6.8
Diluted weighted average shares outstanding	597.2		621.2
Less: participating securities	0.7		0.8
Diluted weighted average common shares outstanding	596.5		620.4
Net earnings per share:
Basic		$4.19		$2.57
Diluted	4.15		2.54


⁽¹⁾	Diluted earnings per share includes any dilutive impact of stock options, restricted stock units, performance-based restricted stock units and performance awards.

The following table includes the number of shares that may be dilutive potential common shares in the future. These shares were not included in the computation of diluted earnings per share because the effect was either antidilutive or the performance condition was not met.



(Shares in millions)	Three months ended March 31
	2018	2017
Performance awards	2.9	5.6
Performance-based restricted stock units	0.5	1.3