Earnings Per Common Share

3 Months Ended

Mar. 31, 2023

Basic earnings per common share is computed by dividing net income by the weighted-average number of common shares outstanding for the period.

Diluted earnings per common share (“Diluted EPS”) takes into account the potential dilution that could occur if outstanding securities were exercised or settled in shares. Dilutive securities that may impact Diluted EPS include shares underlying outstanding stock options, restricted stock units and performance share units granted to employees and non-employee directors (see Note 12), as well as common shares underlying the Convertible Notes (see Note 5). Dilutive securities related to common shares underlying outstanding stock options, restricted stock units, and performance share units granted to employees and non-employee directors are included in the calculation of diluted earnings per common share using the treasury stock method. Dilutive securities related to common shares underlying the Convertible Notes are included in the calculation of diluted earnings per common share using the if-converted method.

Basic and diluted weighted-average common shares outstanding are the same in periods when a net loss is reported or in periods when anti-dilution occurs.

The following table summarizes the computation of basic and diluted earnings per common share (in millions, except per share data):


	Three Months Ended March 31,
		2023		2022
Earnings per common share—basic
Net income		$	25.0	$	86.7
Weighted-average common shares outstanding—basic		185.2		185.1
Earnings per common share—basic		$	0.13	$	0.47
Earnings per common share—diluted
Net income		$	25.0	$	86.7
Interest expense(1)		1.6		1.6
Net income attributable to earnings per common share—diluted		$	26.6	$	88.3

Weighted-average common shares outstanding—basic		185.2		185.1
Convertible Notes weighted-average common shares outstanding(1)		14.7		14.7
Outstanding options, restricted stock units and performance share units		1.6		1.0
Weighted-average common shares outstanding—diluted		201.5		200.8
Earnings per common share—diluted		$	0.13	$	0.44

(1) The If-converted method is used for calculating the dilutive weighted-average shares outstanding related to the Convertible Notes when calculating earnings per common share-diluted. Under this method, interest expense related to the Convertible Notes for the period presented is excluded from net income.

Anti-Dilutive Options and Restricted Stock Units

For the three months ended March 31, 2023 and 2022, approximately 1.2 million and 1.3 million securities outstanding, respectively, comprised of stock options and restricted stock units, were excluded from the calculation of earnings per common share—diluted as they would be anti-dilutive.