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 thirty-nine weeks ended November 2, 2019 and November 3, 2018, there were 139,000 and 119,000 shares of nonvested restricted stock, respectively, excluded from the calculation of diluted earnings per share because of antidilution. For the thirteen weeks ended November 2, 2019 and November 3, 2018, there were 147,000 and 166,000 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 weighted average number of common shares and common stock equivalents outstanding used in calculating diluted earnings per share for the thirty-nine and thirteen week periods ended November 2, 2019 and November 3, 2018:


	Thirty-Nine Weeks Ended
	November 2, 2019	November 3, 2018
Weighted average number of common shares outstanding	11,831,248	13,224,347
Incremental shares from assumed vesting of nonvested restricted stock	10,497	45,058
Weighted average number of common shares and common stock equivalents outstanding	11,841,745	13,269,405


	Thirteen Weeks Ended
	November 2, 2019	November 3, 2018
Weighted average number of common shares outstanding	11,635,707	12,780,472
Incremental shares from assumed vesting of nonvested restricted stock	—	—
Weighted average number of common shares and common stock equivalents outstanding	11,635,707	12,780,472