SHAREHOLDERS' EQUITY

Basic and diluted income per share was determined based on the following share data (in thousands):



	Three Months Ended June 30,		Six Months Ended June 30,
	2018	2017	2018	2017
Weighted average basic common shares	12,416	11,965	12,254	11,896
Effect of stock options	1,176	1,557	1,363	1,564
Effect of dilutive share awards	135	82	177	92
Effect of Convertible Senior Notes and warrants	420	—	733	—
Weighted average diluted common shares	14,147	13,604	14,527	13,552

For each of the three and six months ended June 30, 2018, the weighted average shares that were anti-dilutive, and therefore excluded from the calculation of diluted income per share, included options to purchase 0.4 million shares of common stock.

The 0.625% Convertible Senior Notes due June 1, 2022 and the warrants issued by the Company in the second quarter of 2017 could be converted into the Company’s common stock in the future, subject to certain contingencies. See Note 11—Debt for additional information. Shares of the Company’s common stock associated with these instruments were excluded from the calculation of diluted income per share for the three and six months ended June 30, 2017, as they were anti-dilutive since the conversion price of the Convertible Senior Notes and the strike price of the warrants were greater than the average market price of the Company’s common stock during the second quarter of 2017. Other than the shares associated with the 0.625% Convertible Senior Notes and the warrants, no shares related to potentially dilutive securities were excluded from the calculation of diluted income per share for the three and six months ended June 30, 2017.

Common Stock Repurchases

In each of January 2010, May 2014, January 2016, February 2016 and February 2018, the board of directors authorized and the Company announced the repurchase of up to $10.0 million, $10.0 million, $50.0 million, $40.0 million and $100.0 million, respectively, of LendingTree's common stock. During the six months ended June 30, 2018, the Company purchased 156,731 shares of its common stock pursuant to this stock repurchase program. At June 30, 2018, approximately $81.7 million of the previous authorizations to repurchase common stock remain available for the Company to purchase its common stock.