Earnings Per Share

6 Months Ended

Oct. 31, 2016

We calculate basic earnings per share by dividing net income available to common stockholders by the weighted average number of common shares outstanding during the period. Diluted earnings per share further includes the dilutive effect of stock-based compensation awards. We calculate that dilutive effect using the “treasury stock method” (as defined by GAAP).

The following table presents information concerning basic and diluted earnings per share:



	Three Months Ended				Six Months Ended
	October 31,				October 31,
(Dollars in millions, except per share amounts)	2015		2016		2015		2016
Net income available to common stockholders	$	200	$	197	$	356	$	342
Share data (in thousands):
Basic average common shares outstanding	408,110		389,050		411,116		390,994
Dilutive effect of stock-based awards	2,751		2,798		2,750		2,895
Diluted average common shares outstanding	410,861		391,848		413,866		393,889

Basic earnings per share	$	0.49	$	0.51	$	0.87	$	0.87
Diluted earnings per share	$	0.49	$	0.50	$	0.86	$	0.87

We excluded common stock-based awards for approximately 830,000 shares and 1,937,000 shares from the calculation of diluted earnings per share for the three months ended October 31, 2015 and 2016, respectively. We excluded common stock-based awards for approximately 1,059,000 shares and 1,555,000 shares from the calculation of diluted earnings per share for the six months ended October 31, 2015 and 2016, respectively. We excluded those awards because they were not dilutive for those periods under the treasury stock method.