Earnings per Share

12 Months Ended

Dec. 31, 2018

Earnings Per Share [Abstract]

Earnings per share

Earnings per share

The following table provides a reconciliation between basic and diluted earnings per share:

In millions, except per share data	Year ended December 31,	2018		2017		2016
Net income		$	4,328	$	5,484	$	3,640
Weighted-average basic shares outstanding		734.5		753.6		776.0
Dilutive effect of stock-based compensation		3.2		3.7		3.2
Weighted-average diluted shares outstanding		737.7		757.3		779.2
Basic earnings per share		$	5.89	$	7.28	$	4.69
Diluted earnings per share		$	5.87	$	7.24	$	4.67
Units excluded from the calculation as their inclusion would not have a dilutive effect
Stock options		0.6		0.4		1.2
Performance share units		0.3		0.1		0.2