Earnings Per Share:

Basic earnings per share are computed by dividing net income by the weighted-average number of common shares outstanding during the period. Diluted earnings per share are computed by dividing net income by the sum of the weighted-average number of shares and the number of equivalent shares assumed outstanding, if dilutive, under our stock-based compensation plans.

The computations of basic and diluted earnings per share for Income from continuing operations were as follows (in millions, except per share data):



	For the Years Ended December 31,
	2017			2016			2015
Net income	$	305.7		$	277.8		$	186.6
Add: Loss from discontinued operations	1.4			0.8			0.6
Income from continuing operations	$	307.1		$	278.6		$	187.2

Weighted-average shares outstanding – basic	42.2			43.4			44.9
Add: Potential effect of diluted securities attributable to stock-based payments	0.6			0.6			0.7
Weighted-average shares outstanding – diluted	42.8			44.0			45.6

Earnings per share - Basic:
Income from continuing operations	$	7.28		$	6.41		$	4.17
Loss from discontinued operations	(0.03		)	(0.02		)	(0.01		)
Net income	$	7.25		$	6.39		$	4.16

Earnings per share - Diluted:
Income from continuing operations	$	7.17		$	6.34		$	4.11
Loss from discontinued operations	(0.03		)	(0.02		)	(0.02		)
Net income	$	7.14		$	6.32		$	4.09

An insignificant number of stock appreciation rights were outstanding but not included in the diluted earnings per share calculation because the assumed exercise of such rights would have been anti-dilutive.