10. Earnings Per Share

Basic earnings per share of Class A common stock is calculated by dividing the net income attributable to Cactus Inc. during the period by the weighted average number of shares of Class A common stock outstanding during the same period. Diluted earnings per share of Class A common stock is calculated by dividing the net income attributable to Cactus Inc. during that period by the weighted average number of common shares outstanding assuming all potentially dilutive shares were issued.

Dilution for the period includes the effect of unvested restricted stock units under the treasury method assuming that the proceeds will be used to purchase shares of Class A common stock.

There were no shares of Class A common stock or Class B common stock outstanding prior to February 12, 2018, therefore no earnings per share information has been presented for any period prior to that date.

The following table summarizes the basic and diluted earnings per share calculations:


	Three Months Ended June 30,				Six Months Ended June 30,
	2018		2017		2018		2017
Numerator:
Net income attributable to Cactus Inc.	$	12,334	$	—	$	16,087	$	—
Denominator:
Weighted average Class A shares outstanding—basic		26,450		—		26,450		—
Effect of dilutive shares (1)		329				284
Weighted average Class A shares outstanding—diluted (1)		26,779				26,734		—

Earnings per Class A Share—basic	$	0.47	$	—	$	0.61	$	—
Earnings per Class A Share—diluted (1)	$	0.46	$	—	$	0.60	$	—

(1)

Diluted earnings per share for the periods presented excludes 48,439,772 shares of Class B common stock as the effect would be anti-dilutive.