Basic earnings per share is net earnings divided by the weighted average number of our outstanding common shares, including stock equivalent units where there is no circumstance under which those shares would not be issued. Diluted earnings per share is net earnings divided by the sum of the weighted average number of our outstanding common shares and the effect of our outstanding dilutive potential common shares.


	QUARTER ENDED
SHARES IN THOUSANDS	MARCH 2023		MARCH 2022
Weighted average common shares outstanding – basic		733,163		747,507
Dilutive potential common shares:
Stock options		137		384
Restricted stock units		27		420
Performance share units		219		512
Total effect of outstanding dilutive potential common shares		383		1,316
Weighted average common shares outstanding – dilutive		733,546		748,823

The following shares were not included in the computation of diluted earnings per share because they were either antidilutive or the required performance or market conditions were not met. Some or all of these shares may be dilutive potential common shares in future periods.


	QUARTER ENDED
SHARES IN THOUSANDS	MARCH 2023		MARCH 2022
Stock options		610		—
Performance share units		860		693

On September 22, 2021, we announced that our board of directors approved a new share repurchase program (the 2021 Repurchase Program) under which we are authorized to repurchase up to $1 billion of outstanding shares. Concurrently, the board terminated the remaining repurchase authorization under the share repurchase program approved by the board in February 2019 (the 2019 Repurchase Program).

We repurchased 1,115,560 common shares for approximately $35 million (including transaction fees) under the 2021 Repurchase Program during first quarter 2023. As of March 31, 2023, we had remaining authorization of $342 million for future share repurchases. During first quarter 2022, we repurchased 3,197,675 common shares for approximately $121 million (including transaction fees) under the 2021 Repurchase Program.

All common stock repurchases under the 2021 Repurchase Program were made in open-market transactions. We record share repurchases upon trade date as opposed to the settlement date when cash is disbursed. We record a liability for repurchases that have not yet been settled as of period end. There were 27,139 unsettled shares (approximately $1 million) as of March 31, 2023 and 223,548 unsettled shares (approximately $7 million) as of December 31, 2022.