Earnings per Share

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 March 31,
In millions, except per share amounts	2018			2017
Net loss attributable to common stockholders	$	(7	)	$	(2	)
Weighted average outstanding shares of common stock	121.4			130.4
Dilutive effect of employee stock options, restricted stock and other stock awards	—			—
Common stock and common stock equivalents	121.4			130.4
Net income per share:
Basic	$	(0.06	)	$	(0.02	)
Diluted	$	(0.06	)	$	(0.02	)

For the three months ended March 31, 2018 and 2017, due to the net loss attributable to Teradata common stockholders, potential common shares that would cause dilution, such as employee stock options, restricted stock 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 123.4 million for the three months ended March 31, 2018 and 131.9 million for the three months ended March 31, 2017.

Options to purchase 2.7 million shares of common stock for the three months ended March 31, 2018 and 4.5 million shares of common stock for the three months ended March 31, 2017 were not included in the computation of diluted earnings per share. 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.