Earnings per share (Tables)

12 Months Ended

Jan. 31, 2020

Earnings per share

Schedule of computation of earnings per share

	2019
			Weighted
	Net		Average	Per Share
	Income		Shares	Amount
Basic earnings per share	$	1,712,555	256,553	$	6.68
Effect of dilutive share-based awards			1,500
Diluted earnings per share	$	1,712,555	258,053	$	6.64

	2018
			Weighted
	Net		Average	Per Share
	Income		Shares	Amount
Basic earnings per share	$	1,589,472	265,155	$	5.99
Effect of dilutive share-based awards			950
Diluted earnings per share	$	1,589,472	266,105	$	5.97

	2017
			Weighted
	Net		Average	Per Share
	Income		Shares	Amount
Basic earnings per share	$	1,538,960	272,751	$	5.64
Effect of dilutive share-based awards			611
Diluted earnings per share	$	1,538,960	273,362	$	5.63