6. EARNINGS PER SHARE

Basic earnings per share is computed by dividing net income attributable to WESCO International by the weighted-average number of common shares outstanding during the periods. Diluted earnings per share is computed by dividing net income attributable to WESCO International by the weighted-average common shares and common share equivalents outstanding during the periods. The dilutive effect of common share equivalents is considered in the diluted earnings per share computation using the treasury stock method, which includes consideration of equity awards and contingently convertible debt.

The following table sets forth the details of basic and diluted earnings per share:



	Three Months Ended					Nine Months Ended
	September 30,					September 30,
(In thousands, except per share data)	2017		2016			2017		2016
Net income (loss) attributable to WESCO International, Inc.	$	53,675	$	(31,611	)	$	140,918	$	54,243
Weighted-average common shares outstanding used in computing basic earnings per share	47,415		43,378			48,134		42,611
Common shares issuable upon exercise of dilutive equity awards	389		511			508		519
Common shares issuable from contingently convertible debentures (see below for basis of calculation)	—		4,851			—		4,908
Weighted-average common shares outstanding and common share equivalents, diluted	47,804		48,740			48,642		48,038
Weighted-average common shares outstanding and common share equivalents used in computing diluted earnings per share	47,804		43,378			48,642		48,038
Earnings (loss) per share attributable to WESCO International, Inc.
Basic	$	1.13	$	(0.73	)	$	2.93	$	1.27
Diluted	$	1.12	$	(0.73	)	$	2.90	$	1.13

For the three and nine months ended September 30, 2017, the computation of diluted earnings per share attributable to WESCO International, Inc. excluded stock-based awards of approximately 1.5 million and 1.3 million, respectively. For the three and nine months ended September 30, 2016, the computation of diluted (loss) earnings per share attributable to WESCO International, Inc. excluded stock-based awards of approximately 1.3 million. These amounts were excluded because their effect would have been antidilutive.

Because of WESCO’s previous obligation to settle the par value of the 6.0% Convertible Senior Debentures due 2029 (the "2029 Debentures") in cash upon conversion, WESCO was required to include shares underlying the 2029 Debentures in its diluted weighted-average shares outstanding when the average stock price per share for the period exceeded the conversion price of the debentures. Only the number of shares that would have been issuable under the treasury stock method of accounting for share dilution were included, which was based upon the amount by which the average stock price exceeded the conversion price. The conversion price of the 2029 Debentures was $28.87 and the maximum amount of share dilution was limited to 11,951,932 shares. Since the 2029 Debentures were redeemed on September 15, 2016, there was no dilution from contingently convertible debentures for the three and nine months ended September 30, 2017. As a result of the net loss attributable to WESCO International, Inc. for the three months ended September 30, 2016, dilutive shares were not included in the calculation of diluted loss per share because their effect was antidilutive. For the nine months ended September 30, 2016, the effect of the 2029 Debentures on diluted earnings per share attributable to WESCO International, Inc. was a decrease of $0.13.

In December 2014, the Company's Board of Directors authorized the repurchase of up to $300 million of the Company's common stock through December 31, 2017. As of December 31, 2016, WESCO had repurchased 2,468,576 shares of the Company's common stock for $150.0 million under this repurchase authorization. During the three months ended June 30, 2017, the Company repurchased 804,291 shares under the repurchase authorization for $50.0 million. On August 7, 2017, the Company entered into an accelerated stock repurchase agreement (the "ASR Transaction") with a financial institution to repurchase additional shares of its common stock. In exchange for an up-front cash payment of $50.0 million, the Company received 974,246 shares. The total number of shares ultimately delivered under the ASR Transaction was determined by the average of the volume-weighted average prices of the Company's common stock for each exchange business day during the settlement valuation period. WESCO funded the repurchase with borrowings under the Company's revolving credit facility and accounts receivable securitization facility. For purposes of computing earnings per share, share repurchases have been reflected as a reduction to common shares outstanding on the respective delivery dates.