NET EARNINGS PER SHARE

Our basic and diluted earnings per share were:


•	$0.42 during second quarter 2018 and $0.77 during year-to-date 2018;


•	$0.03 during second quarter 2017 and $0.24 during year-to-date 2017.

Basic earnings per share is net earnings divided by the weighted average number of our outstanding common shares, including stock equivalent units where there is no circumstance under which those shares would not be issued. Diluted earnings per share is net earnings divided by the sum of the weighted average number of our outstanding common shares and the effect of our outstanding dilutive potential common shares:



	QUARTER ENDED		YEAR-TO-DATE ENDED
SHARES IN THOUSANDS	JUNE 2018	JUNE 2017	JUNE 2018	JUNE 2017
Weighted average common shares outstanding – basic	757,829	752,630	757,317	751,674
Dilutive potential common shares:
Stock options	1,628	2,845	1,655	2,913
Restricted stock units	512	488	540	518
Performance share units	564	488	480	520
Total effect of outstanding dilutive potential common shares	2,704	3,821	2,675	3,951
Weighted average common shares outstanding – dilutive	760,533	756,451	759,992	755,625

We use the treasury stock method to calculate the dilutive effect of our outstanding stock options, restricted stock units and performance share units. Share-based payment awards that are contingently issuable upon the achievement of specified performance or market conditions are included in our diluted earnings per share calculation in the period in which the conditions are satisfied.

Potential Shares Not Included in the Computation of Diluted Earnings per Share

The following shares were not included in the computation of diluted earnings per share because they were either antidilutive or the required performance or market conditions were not met. Some or all of these shares may be dilutive potential common shares in future periods.



	QUARTER ENDED		YEAR-TO-DATE ENDED
SHARES IN THOUSANDS	JUNE 2018	JUNE 2017	JUNE 2018	JUNE 2017
Stock options	—	1,408	—	1,408
Performance share units	486	450	486	450