Earnings Per Share

9 Months Ended

Sep. 30, 2023

Basic earnings per common share is computed by dividing net income available to common stockholders by the weighted average of common shares outstanding during the period. Diluted earnings per common share adjusts basic earnings per common share for the effects of stock options and restricted stock in the periods where such items are dilutive.

On December 1, 2021, our Board of Directors approved a share repurchase authorization of up to $1 billion that expires December 31, 2026, and excludes excise tax. As of September 30, 2023, approximately $41.0 million remained under the 2021 authorization. In addition, on May 2, 2023, we announced that our Board of Directors approved a new share repurchase authorization of up to $1.5 billion to begin upon completion of the current $1 billion authorization and to be executed by December 31, 2028. For the nine months ended September 30, 2023, the Company repurchased 584,086 shares of common stock for an average price of $298.12 per share including brokerage fees and excise tax. For the nine months ended September 30, 2022, 2,482,804 shares were repurchased for an average price of $228.33 per share.

The following tables provide a reconciliation of basic and diluted earnings per share computations for the three and nine months ended September 30, 2023 and 2022:


	Three Months Ended September 30,				Nine Months Ended September 30,
(Millions of dollars, except share and per share amounts)	2023		2022		2023		2022
Earnings per common share:
Net income per share - basic


Net income attributable to common stockholders	$	167.7	$	219.5	$	406.8	$	555.2

Weighted average common shares outstanding (in thousands)	21,401		23,206		21,635		23,963

Earnings per common share	$	7.83	$	9.46	$	18.80	$	23.17


	Three Months Ended March 31,				Nine Months Ended September 30,
(Millions of dollars, except share and per share amounts)	2023		2022		2023		2022
Earnings per common share - assuming dilution:
Net income per share - diluted


Net income attributable to common stockholders	$	167.7	$	219.5	$	406.8	$	555.2

Weighted average common shares outstanding (in thousands)	21,401		23,206		21,635		23,963
Common equivalent shares:
Dilutive share-based awards	389		444		385		435
Weighted average common shares outstanding - assuming dilution (in thousands)	21,790		23,650		22,020		24,398

Earnings per common share assuming dilution	$	7.69	$	9.28	$	18.47	$	22.76

We have excluded from the earnings-per-share calculation certain stock options and shares that are considered to be anti-dilutive under the treasury stock method and are reported in the table below.


	Three Months Ended September 30,		Nine Months Ended September 30,
Potentially dilutive shares excluded from the calculation as their inclusion would be anti-dilutive	2023	2022	2023	2022
Stock Options	38,100	—	38,100	3,250
PSUs	—	—	12,800	1,353
Total anti-dilutive shares	38,100	—	50,900	4,603