Share-Based Payments (Tables)

12 Months Ended

Apr. 30, 2022

Share-based Payment Arrangement [Abstract]

Weighted-average Black-Scholes assumptions for stock options granted

The fair value of each stock option is estimated on the date of grant using a Black-Scholes option-pricing model with the following weighted-average assumptions for stock options granted:

	2022		2021		2020
Expected volatility (%)	24.0	%	23.0	%	20.1	%
Dividend yield (%)	2.7	%	3.2	%	2.8	%
Risk-free interest rate (%)	1.0	%	0.4	%	1.9	%
Expected life of stock options (years)	6.0		6.0		6.0

Summary of the Company's stock option activity and related information

The following table is a summary of our stock option activity.

	Number of  Stock Options	Weighted-Average Exercise Price
Outstanding at May 1, 2021	720,083	$	113.48
Granted	152,971	135.53
Exercised	(145,312)	112.22
Outstanding at April 30, 2022	727,742	$	118.37
Exercisable at April 30, 2022	343,526	$	115.23

Summary of restricted shares, deferred shares, deferred stock units, and performance units

The following table is a summary of our restricted shares, deferred stock units, and performance units.

	Restricted  Shares and Deferred Stock Units	Weighted- Average Grant Date Fair Value Per Share		Performance Units	Weighted- Average Grant Date Fair Value Per Share
Outstanding at May 1, 2021	598,738	$	116.54	325,453	$	118.21
Granted	66,514	135.10		171,907	135.53
Vested	(179,584)	121.07		—	—
Forfeited	(54,613)	118.71		(34,883)	123.90
Outstanding at April 30, 2022	431,055	$	117.24	462,477	$	124.22

Weighted-average grant date fair values of the equity awards

The following table summarizes the weighted-average fair values of the equity awards granted.

Year Ended April 30,	Restricted  Shares and Deferred Stock Units	Weighted- Average Grant Date Fair Value Per Share		Performance Units	Weighted- Average Grant Date Fair Value Per Share
2022	66,514	$	135.10	171,907	$	135.53
2021	83,188	110.66		194,786	113.70
2020	245,945	121.19		168,212	123.68