Net Income Per Share

3 Months Ended

Mar. 31, 2021

Basic net income per share is computed by dividing net income by the weighted average number of shares of Common Stock and Class A Stock outstanding. Net income per share is presented on a combined basis, inclusive of Common Stock and Class A Stock outstanding, as each class of stock has equivalent economic rights. Diluted net income per share includes the potential dilutive effect of other securities as if such securities were converted or exercised during the period, when the effect is dilutive. The calculations of basic and diluted net income per share are as follows:


	Three Months Ended March 31,
(In millions, except per share data)	2021		2020
Net income - basic and diluted	$	1,115.2	$	624.6

Weighted average shares - basic	105.4		109.8
Effect of dilutive securities:
Stock options	4.5		5.0
Restricted stock	0.6		0.3
Weighted average shares - diluted	110.5		115.1

Net income per share - basic	$	10.58	$	5.69
Net income per share - diluted	$	10.09	$	5.43

Shares which have been excluded from diluted per share amounts because their effect would have been antidilutive, include the following:


	Three Months Ended March 31,
(Shares in millions)	2021	2020
Stock options	5.0	10.2