Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 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 September 30		For the nine months ended September 30
(in millions)	2017	2016	2017	2016
Weighted-average basic shares outstanding	145.5	147.3	146.2	150.7
Dilutive effect of stock options	0.3	1.0	0.4	0.9
Weighted-average diluted shares outstanding	145.8	148.3	146.6	151.6