Earnings per Share

6 Months Ended

Jun. 30, 2021

Basic earnings per share is calculated by dividing net income by the weighted average number of shares outstanding during the reported period. The calculation of diluted earnings per share is similar to basic earnings per share, except that the weighted average number of shares outstanding includes the dilution from potential shares resulting from stock options, restricted stock awards and other stock awards. The components of basic and diluted earnings per share are as follows:


	Three Months Ended June 30,				Six Months Ended June 30,
In millions, except per share amounts	2021		2020		2021		2020
Net income (loss) attributable to common stockholders	$	44	$	(43)	$	97	$	125
Weighted average outstanding shares of common stock	109.0		108.5		108.9		109.4
Dilutive effect of employee stock options, restricted stock and other stock awards	3.7		—		3.8		1.2
Common stock and common stock equivalents	112.7		108.5		112.7		110.6
Net income (loss) per share:
Basic	$	0.40	$	(0.40)	$	0.89	$	1.14
Diluted	$	0.39	$	(0.40)	$	0.86	$	1.13

For the three months ended June 30, 2020, due to the net loss attributable to Teradata common stockholders, potential shares that would cause dilution, such as shares resulting from employee stock options, restricted shares and other stock awards, have been excluded from the diluted share count because their effect would have been anti-dilutive. The fully diluted shares would have been 109.7 million for the three months ended June 30, 2020.

Options to purchase 0.2 million and 0.6 million shares of common stock for the three and six months ended June 30, 2021 and 2.1 million and 2.2 million shares of common stock for the three and six months ended June 30, 2020 were not included in the computation of diluted earnings per share because the exercise prices of these options were greater than the average market price of the common shares for the period, and therefore would have been anti-dilutive.