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 3, 2018 and October 28, 2017, there were 119,000 and 137,000 shares of nonvested restricted stock, respectively, excluded from the calculation of diluted earnings per share because of antidilution. For the thirteen weeks ended November 3, 2018 and October 28, 2017, there were 166,000 and 124,000 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 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 thirty-nine and thirteen week periods ended November 3, 2018 and October 28, 2017:


	Thirty-Nine Weeks Ended
	November 3, 2018	October 28, 2017
Average number of common shares outstanding	13,224,347	14,221,388
Incremental shares from assumed vesting of nonvested restricted stock	45,058	49,030
Average number of common shares and common stock equivalents outstanding	13,269,405	14,270,418


	Thirteen Weeks Ended
	November 3, 2018	October 28, 2017
Average number of common shares outstanding	12,780,472	13,563,295
Incremental shares from assumed vesting of nonvested restricted stock	—	51,109
Average number of common shares and common stock equivalents outstanding	12,780,472	13,614,404