Earnings Per Share

Diluted weighted average shares is calculated as basic weighted average shares plus the effect, calculated using the treasury stock method, of assuming that restricted share units, performance share units and purchase match units have vested. The following table provides the weighted average number of common shares outstanding used in the calculation of the Company's basic and diluted earnings per share:



(In thousands, except per share data)	Three Months Ended June 30					Six Months Ended June 30
(In thousands, except per share data)	2018		2017			2018		2017
Weighted average number of common shares outstanding, basic	53,610		53,402			53,567		53,359
Dilutive effect of securities:
Restricted Share Units	69		77			75		77
Performance Share Units	42		105			54		113
Purchase Match Units	20		23			20		22
Weighted average number of common shares outstanding, diluted	53,741		53,607			53,716		53,571
Effect of dilutive shares on earnings per share	$	—	$	(0.01	)	$	—	$	—

All dilutive common share equivalents are reflected in the earnings per share calculation while antidilutive common share equivalents are not reflected in the earnings per share calculation. The diluted weighted average number of common shares outstanding for the three and six months ended June 30, 2018 excludes approximately 8,000 common share equivalents issuable under the Company's stock compensation plans, as their effect would be antidilutive. There were no common share equivalents that were antidilutive for the three and six months ended June 30, 2017.