Earnings Per Share (Tables)

3 Months Ended

Mar. 31, 2017

Earnings Per Share [Abstract]

Number of Shares Used In the Earnings Per Share Calculations

The number of shares used in earnings per share calculations is reconciled as follows:

	For the three months ended March 31
(in millions)	2017	2016
Weighted-average basic shares outstanding	146.5	153.0
Dilutive effect of stock options	0.6	0.8
Weighted-average diluted shares outstanding	147.1	153.8