The calculations of basic and diluted EPS are based on the weighted average number of shares of common stock and potential common stock outstanding during the period. Diluted EPS includes the incremental effects of the various long-term incentive compensation plans and ATM forward sale agreements under the treasury stock method when the impact would be dilutive. For the purposes of determining diluted EPS, for the twelve months ended December 31, 2023, the shares underlying the purchase contracts included within the Equity Units were included in the calculation of potential common stock outstanding using the if-converted method under US GAAP and we assumed share settlement of the remaining purchase contract payment balance from our Equity Units based on the average share price during the period. This method assumes conversion at the beginning of the reporting period, or at time of issuance, if later. The purchase contracts were settled on December 1, 2023. For the purchase contracts, the number of shares of our common stock that would have been issuable at the end of each reporting period prior to the settlement date were reflected in the denominator of our diluted EPS calculation. A numerator adjustment was reflected in the calculation of diluted EPS for interest expense incurred in 2023, net of tax, related to the purchase contracts.

The shares underlying the Series C Mandatory Convertible Preferred Stock included within the Equity Units were contingently convertible as the conversion was contingent on a successful remarketing. Contingently convertible shares where conversion was not tied to a market price trigger were excluded from the calculation of diluted EPS until such time as the contingency had been resolved under the if-converted method. The unsuccessful remarketing resolved the contingency and no shares were reflected in the denominator for the years ended December 31, 2023, for the calculation of diluted EPS.

We began using the two-class method of computing earnings per share in 2023 because we have participating securities in the form of non-vested restricted stock units with a non-forfeitable right to dividend equivalents, for which vesting is predicated solely on the passage of time. The calculation of earnings per share using the two-class method excludes income attributable to these participating securities from the numerator and excludes the dilutive impact of those shares from the denominator.

Basic net income per share is computed by dividing net income available to common shareholders by the weighted-average number of shares of common stock outstanding during the period. Diluted net income per share is computed by giving effect to all potential shares of common stock, to the extent they are dilutive. Refer to Note 6, "Equity," for additional information.

The following table presents the calculation of our basic and diluted EPS:


Year Ended December 31, (in millions, except per share amounts)	2025		2024		2023
Numerator:
Net Income Available to Common Shareholders	$	929.5	$	739.7	$	661.7
Less: Income allocated to participating securities	2.6		1.6		0.6
Net Income Available to Common Shareholders - Basic	$	926.9	$	738.1	$	661.1
Add: Dilutive effect of Equity Units	—		—		1.4
Net Income Available to Common Shareholders - Diluted	$	926.9	$	738.1	$	662.5
Denominator:
Average common shares outstanding - Basic	472.9		454.2		416.1
Dilutive potential common shares:
Equity Units purchase contracts	—		—		29.8
Equity Units purchase contract payment balance	—		—		0.9
Shares contingently issuable under employee stock plans	1.2		0.9		0.7
Shares restricted under employee stock plans	0.3		0.3		0.4
ATM Forward sale agreements	0.1		0.6		—
Average Common Shares - Diluted	474.5		456.0		447.9
Earnings per common share:
Basic	$	1.96	$	1.63	$	1.59
Diluted	$	1.95	$	1.62	$	1.48