8.	Capital Stock

The Company’s authorized capital stock consists of 25 million shares of preferred stock, par value $.001 per share, 500 million shares of Class A common stock, par value $.001 per share, and 100 million shares of Class B common stock, par value $.001 per share. The shares of Class A common stock and Class B common stock are identical in all respects, except for voting rights and certain conversion rights and transfer restrictions, as follows: (1) each share of Class A common stock entitles the holder to one vote on matters submitted to a vote of the Company’s stockholders and each share of Class B common stock entitles the holder to ten votes on each such matter; (2) stock dividends of Class A common stock may be paid only to holders of Class A common stock and stock dividends of Class B common stock may be paid only to holders of Class B common stock; (3) if a holder of Class B common stock transfers such shares to a person other than a permitted transferee, as defined in the Company’s Certificate of Incorporation, such shares will be converted automatically into shares of Class A common stock; and (4) Class A common stock has no conversion rights; however, each share of Class B common stock is convertible into one share of Class A common stock, in whole or in part, at any time at the option of the holder. All outstanding Class B shares have been converted to Class A shares. As of December 31, 2018 and 2017, there were no preferred or Class B common shares outstanding.

Weighted-average common shares outstanding

The following is a reconciliation of the weighted-average common shares outstanding for purposes of computing basic and diluted net income per share (in thousands):

	Year Ended December 31,
	2018		2017		2016

Basic weighted-average common shares outstanding		55,170		52,806		55,412
Effect of dilutive securities:
Stock awards and options		1,061		1,110		683
Convertible note		245		936		2
Diluted weighted-average common shares outstanding		56,476		54,852		56,097

For the years ended December 31, 2018, 2017 and 2016, other stock options totaling 0.9 million, 0.4 million and 2.0 million, respectively, were excluded from the calculation of diluted earnings per share because they were anti-dilutive. The convertible notes have a dilutive impact on EPS when the average market price of the Company’s common stock for a given period exceeds the initial conversion price. See Note 6 for discussion of initial conversion price and conversion rate.

Dividends

Quarterly cash dividends for the years ended December 31, 2018 and 2017 totaled $80.6 million and $76.1 million or $0.365 per share in all quarters of 2018 and $0.36 for all quarters of 2017. The board of directors has declared a quarterly cash dividend of $0.37 per share of Class A common stock to be paid on March 13, 2019 to stockholders of record on February 25, 2019.

Repurchases of common stock

In 1998, the Company’s board of directors approved a stock repurchase plan authorizing the Company to repurchase $10.0 million of its outstanding shares of Class A common stock on the open market or in private transactions. The Company’s board from time to time increased the amount authorized under the 1998 stock repurchase plan, including an increase of $400.0 million announced in August 2013. In October 2015, the Company’s board terminated the 1998 stock repurchase plan and approved a new repurchase plan with an initial authorization amount of $500.0 million. In July 2018, the Company’s board of directors terminated the 2015 stock repurchase plan and approved a new repurchase plan with an initial authorization amount of $500 million. The repurchases are used primarily for strategic initiatives and to offset dilution from the Company’s equity incentive plans and from conversion of the Convertible Notes. During the years ended December 31, 2018, 2017 and 2016, the Company repurchased 0.5 million, 1.2 million and 4.5 million shares of Class A common stock under the 2015 plan for an aggregate price of $40.6 million, $71.7 million and $247.2 million, respectively. During the year ended December 31, 2018 we purchased 0.4 shares under the 2018 plan for $29.0 million At December 31, 2018, $471.0 million was available for repurchases under the 2018 stock repurchase plan.