Earnings Per Share

9 Months Ended

Sep. 30, 2021

Basic earnings per share (“EPS”) is computed by dividing net income attributable to Amkor common stockholders by the weighted-average number of common shares outstanding during the period. The weighted-average number of common shares outstanding is reduced for treasury stock.

Diluted EPS is computed based on the weighted-average number of common shares outstanding plus the effect of dilutive potential common shares outstanding during the period. Dilutive potential common shares include outstanding stock options, performance-vested restricted stock units, time-vested restricted stock units and unvested restricted shares.

The following table summarizes the computation of basic and diluted EPS:


	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2021		2020		2021		2020
	(In thousands, except per share data)
Net income attributable to Amkor common stockholders	$	180,854	$	92,151	$	426,469	$	211,464




Weighted-average number of common shares outstanding - basic	244,100		241,675		243,746		241,232
Effect of dilutive securities:
Share-based awards	1,842		917		1,865		705
Weighted-average number of common shares outstanding - diluted	245,942		242,592		245,611		241,937
Net income attributable to Amkor per common share:
Basic	$	0.74	$	0.38	$	1.75	$	0.88
Diluted	0.74		0.38		1.74		0.87

The following table summarizes the potential shares of common stock that were excluded from diluted EPS because the effect of including these potential shares was anti-dilutive:


	For the Three Months Ended September 30,		For the Nine Months Ended September 30,
	2021	2020	2021	2020
	(In thousands)
Share-based awards	180	858	90	2,943