10. EARNINGS PER SHARE

Basic earnings per share (EPS) is calculated by dividing net income or loss attributable to NCR less any dividends, accretion or decretion, redemption or induced conversion on our Series A Convertible Preferred Stock, by the weighted average number of shares outstanding during the reported period.

In computing diluted EPS, we adjust the numerator used in the basic EPS computation, subject to anti-dilution requirements, to add back the dividends (declared or cumulative undeclared) applicable to the Series A Convertible Preferred Stock. Such add-back would also include any adjustments to equity in the period to accrete the Series A Convertible Preferred Stock to its redemption price, or recorded upon a redemption or induced conversion. We adjust the denominator used in the basic EPS computation, subject to anti-dilution requirements, to include the dilution from potential shares resulting from the issuance of the Series A Convertible Preferred Stock, restricted stock units, and stock options. The Company includes the potential windfall or shortfall tax benefits as well as average unrecognized compensation expense as part of the assumed proceeds from exercises of stock options. The Company uses the tax law ordering approach to determine the potential utilization of windfall benefits.

The holders of Series A Convertible Preferred Stock and unvested restricted stock units do not have nonforfeitable rights to common stock dividends or common stock dividend equivalents and therefore do not qualify as participating securities. See Note 6, "Stock Compensation Plans," for share information on NCR’s stock compensation plans.

During the three months ended March 31, 2016, the Company repurchased 8.6 million shares of its common stock for $209 million, and paid $4 million for 0.1 million shares of its common stock that were retired on April 1, 2016. During the three months ended March 31, 2015, the Company repurchased zero shares of its common stock. Upon repurchase, shares are retired.

The components of basic and diluted earnings per share are as follows:



In millions, except per share amounts	Three months ended March 31
In millions, except per share amounts	2016			2015
Amounts attributable to NCR common stockholders:
Income from continuing operations	$	32		$	40
Income from discontinued operations, net of tax	—			—
Net income attributable to NCR	$	32		$	40
Dividends on convertible preferred stock	(11		)	—
Net income attributable to NCR common stockholders	21			40
Weighted average outstanding shares of common stock:
Basic weighted average number of shares outstanding	130.4			169.0
Dilutive effect of employee stock options and restricted stock units	2.3			2.6
Diluted weighted average number of shares outstanding	132.7			171.6
Basic earnings per share:
From continuing operations	$	0.16		$	0.24
From discontinued operations	—			—
Total basic earnings per share	$	0.16		$	0.24
Diluted earnings per share:
From continuing operations	$	0.16		$	0.23
From discontinued operations	—			—
Total diluted earnings per share	$	0.16		$	0.23

For the three months ended March 31, 2016, it was more dilutive to assume the Series A Convertible Preferred Stock was not converted to common stock and therefore weighted average outstanding shares of common stock were not adjusted by the as-if converted Series A Convertible Preferred Stock because the effect would have been anti-dilutive. If the as-if converted Series A Convertible Preferred Stock had been dilutive, approximately 27.7 million additional shares would have been included in the diluted weighted average number of shares outstanding for the quarter ended March 31, 2016.

Additionally, during the three months ended March 31, 2016 and 2015, there were 0.8 million and 0.5 million weighted anti-dilutive restricted stock units outstanding, respectively.