Note 6—Earnings Per Share

Basic earnings per share (“EPS”) is computed by dividing net income attributable to Amphenol Corporation by the weighted average number of common shares outstanding. Diluted EPS is computed by dividing net income attributable to Amphenol Corporation by the weighted average number of common shares and dilutive common shares outstanding, which relates to stock options. A reconciliation of the basic weighted average common shares outstanding to diluted weighted average common shares outstanding for the three and nine months ended September 30, 2017 and 2016 is as follows:


	Three Months Ended September 30,				Nine Months Ended September 30,
(dollars and shares in millions, except per share data)	2017		2016		2017		2016
Net income attributable to Amphenol Corporation shareholders	$	277.5	$	224.3	$	753.9	$	587.5
Basic weighted average common shares outstanding		305.0		308.9		305.8		308.3
Effect of dilutive stock options		10.7		6.8		10.3		6.8
Diluted weighted average common shares outstanding		315.7		315.7		316.1		315.1
Earnings per share attributable to Amphenol Corporation shareholders:
Basic	$	0.91	$	0.73	$	2.47	$	1.91
Diluted	$	0.88	$	0.71	$	2.39	$	1.86

Excluded from the computations above were anti-dilutive common shares of 5.3 million and 13.2 million for the three months ended September 30, 2017 and 2016, respectively and 2.1 million and 11.0 million for the nine months ended September 30, 2017 and 2016, respectively.

In addition to the impact on the provision for income taxes discussed in Note 2 herein, the adoption of ASU 2016-09 in 2017 requires that excess tax benefits and tax deficiencies be excluded from the assumed proceeds available in calculating the dilutive effect of stock options under the treasury stock method. As required, the Company adopted this provision of the new standard prospectively, which had the effect of increasing the Company’s diluted weighted average common shares outstanding by approximately two million shares for both the three and nine months ended September 30, 2017.