Earnings and Dividends per Share (Notes)

3 Months Ended

Mar. 31, 2020

Earnings and Dividends Per Share [Abstract]

Earnings per Share

Earnings and Dividends per Share

Earnings per Share

The Company has unvested restricted stock units outstanding that are considered participating securities and, therefore, computes basic and diluted earnings per share under the two-class method. Basic earnings per share for the periods are based upon the weighted average number of shares of common stock outstanding during each period. Diluted earnings per share include the effects of certain stock options and performance stock units.

	Three Months Ended March 31,
	2020		2019
Net income attributable to Westlake Chemical Corporation	$	145	$	72
Less:
Net income attributable to participating securities	—		(1		)
Net income attributable to common shareholders	$	145	$	71

The following table reconciles the denominator for the basic and diluted earnings per share computations shown in the consolidated statements of operations:

	Three Months Ended March 31,
	2020		2019
Weighted average common shares—basic	128,237,364		128,528,480
Plus incremental shares from:
Assumed exercise of options and vesting of performance stock units	205,608		385,441
Weighted average common shares—diluted	128,442,972		128,913,921
Earnings per common share attributable to Westlake Chemical Corporation:
Basic	$	1.13	$	0.56
Diluted	$	1.13	$	0.55

Excluded from the computation of diluted earnings per share are options to purchase 1,099,638 and 320,473 shares of common stock for the three months ended March 31, 2020 and 2019, respectively. These options were outstanding during the periods reported but were excluded because the effect of including them would have been antidilutive.

Dividends per Share

Dividends per common share for the three months ended March 31, 2020 and 2019 were as follows:

	Three Months Ended March 31,
	2020		2019
Dividends per common share	$	0.2625	$	0.2500