Earnings Per Share

9 Months Ended

Sep. 30, 2020

Basic earnings per share is calculated by dividing net income attributable to controlling interests by the weighted-average number of shares of common stock outstanding. Diluted earnings per share is similar to basic earnings per share, but is adjusted for the effect of potentially issuable common stock, except when inclusion is antidilutive.

The calculation of basic and diluted earnings per share of common stock is as follows (dollars in millions, except per share data):


	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Numerator:
Net income attributable to controlling interests	$	37.2	$	75.4	$	88.7	$	156.1
Less: Total income available to participating unvested securities(1)	—		—		—		(0.1)
Total net income attributable to common stock	$	37.2	$	75.4	$	88.7	$	156.0
Denominator:
Weighted-average shares of common stock outstanding—basic	80,001,360		89,970,871		81,832,607		92,996,289
Potential shares of common stock:
Restricted stock units	115,155		1,429		48,915		79,775
Employee stock options	735,023		—		245,008		—
Weighted-average shares of common stock outstanding—diluted	80,851,538		89,972,300		82,126,530		93,076,064
Earnings per share of common stock attributable to controlling interests:
Basic	$	0.46	$	0.84	$	1.08	$	1.68
Diluted	$	0.46	$	0.84	$	1.08	$	1.68

(1)Income available to participating unvested securities includes dividends paid on unvested restricted shares and their proportionate share of undistributed earnings.

Employee options to purchase 8,970,000 shares were not included in the computation of diluted EPS for the three and nine months ended September 30, 2019 because the assumed proceeds from exercising such options exceed the average price of the shares of common stock for the period and, therefore, the options are deemed antidilutive.