Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2018

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)	2018	2017	2018	2017
Weighted-average basic shares outstanding	142.6	145.5	143.2	146.2
Dilutive effect of stock options	0.5	0.3	0.5	0.4
Weighted-average diluted shares outstanding	143.1	145.8	143.7	146.6