7. Earnings Per Share

9 Months Ended

Sep. 30, 2021

. EARNINGS PER SHARE

Basic earnings per share is computed by dividing net income attributable to Bio-Rad by the weighted average number of common shares outstanding for that period. Diluted earnings per share takes into account the effect of dilutive securities, such as stock options and restricted stock, and uses the average share price for the period in determining the number of potential common shares that are to be added to the weighted average number of shares outstanding. Potential common shares are excluded from the diluted earnings per share calculation if the effect of including such securities would be anti-dilutive.

The weighted average number of common shares outstanding used to calculate basic and diluted earnings per share, and the anti-dilutive shares that are excluded from the diluted earnings per share calculation are as follows (in thousands):


	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2021	2020	2021	2020
Basic weighted average shares outstanding	29,814	29,721	29,800	29,746
Effect of potentially dilutive stock options and restricted stock awards	410	407	390	391
Diluted weighted average common shares outstanding	30,224	30,128	30,190	30,137
Anti-dilutive shares	32	41	18	17