4. Earnings per Share

Basic earnings per common share amounts are calculated using the weighted average number of common shares outstanding for the period. Diluted earnings per common share amounts are calculated using the weighted average number of common shares outstanding plus the additional dilution for all potentially dilutive securities, such as nonvested restricted stock. During loss periods, diluted loss per share amounts are based on the weighted average number of common shares outstanding, because the inclusion of common stock equivalents would be antidilutive.

The dilutive effect of stock-based compensation arrangements is accounted for using the treasury stock method. The Company includes as assumed proceeds the amount of compensation cost attributed to future services and not yet recognized. For the thirteen weeks ended May 4, 2019 and May 5, 2018, there were 128,000 and 108,000 shares of nonvested restricted stock, respectively, excluded from the calculation of diluted earnings per share because of antidilution.

The following table provides a reconciliation of the weighted average number of common shares outstanding used to calculate basic earnings per share to the number of common shares and common stock equivalents outstanding used in calculating diluted earnings per share for the thirteen week periods ended May 4, 2019 and May 5, 2018:


	Thirteen Weeks Ended
	May 4, 2019	May 5, 2018
Weighted average number of common shares outstanding	11,976,142	13,578,100
Incremental shares from assumed vesting of nonvested restricted stock	30,164	53,166
Weighted average number of common shares and common stock equivalents outstanding	12,006,306	13,631,266