Stock-Based Compensation (Tables)

12 Months Ended

May 31, 2021

Share-based Payment Arrangement, Noncash Expense [Abstract]

Assumptions Used to Determine Fair Value of Options

The fair value of options was estimated at the date of grant using a Black-Scholes option-pricing model with the following assumptions for the fiscal years ended May 31:

	2021		2020		2019
Risk-free interest rate	0.4	%	1.9	%	2.7	%
Dividend yield	1.1	%	1.1	%	1.2	%
Expected volatility of Cintas' common stock	23.5	%	19.0	%	17.9	%
Expected life of the option in years	5.5		6.0		6.0

Stock Options Granted and Outstanding

The information presented in the following table relates primarily to stock options granted and outstanding under either the 2016 Plan or under previously adopted plans:

	Shares	Weighted Average Exercise Price
Outstanding, June 1, 2018 (2,006,922 shares exercisable)	8,930,186	$	96.71
Granted	1,013,005	219.37
Canceled	(3,045)	58.03
Forfeited	(397,304)	155.39
Exercised	(1,333,908)	54.14
Outstanding, May 31, 2019 (1,919,976 shares exercisable)	8,208,934	123.80
Granted	575,813	250.50
Canceled	(5,432)	72.17
Forfeited	(312,391)	185.08
Exercised	(1,361,525)	70.03
Outstanding, May 31, 2020 (1,913,374 shares exercisable)	7,105,399	145.54
Granted	747,550	348.24
Canceled	(1,452)	59.51
Forfeited	(91,722)	193.94
Exercised	(1,704,251)	83.31
Outstanding, May 31, 2021 (1,548,867 shares exercisable)	6,055,524	$	191.11

Summary of Information Related to Stock Options Outstanding

The following table summarizes the information related to stock options outstanding at May 31, 2021:

		Outstanding Options			Exercisable Options
Range of Exercise Prices	Number Outstanding	Average Remaining Option Life	Weighted Average Exercise Price		Number Exercisable	Weighted Average Exercise Price
$28.14 - $108.39	1,621,375	3.93	$	83.28	1,248,866	$	75.94
$108.40 - $204.48	1,329,236	6.30	143.30		280,610	137.55
$204.49 - $260.79	1,865,666	7.58	228.36		6,752	230.79
$260.80 - $361.09	1,239,247	9.61	327.37		12,639	277.33
$28.14 - $361.09	6,055,524	6.74	$	191.11	1,548,867	$	89.42

Restricted Stock Awards Granted and Outstanding

The information presented in the following table relates to restricted stock awards granted and outstanding under either the 2016 Plan or under previously adopted plans:

	Shares	Weighted Average Grant Price
Outstanding, unvested grants at June 1, 2018	2,641,114	$	122.18
Granted	425,614	221.27
Forfeited	(109,393)	169.48
Vested	(765,647)	93.37
Outstanding, unvested grants at May 31, 2019	2,191,688	149.12
Granted	228,292	248.39
Forfeited	(135,934)	208.37
Vested	(658,831)	113.93
Outstanding, unvested grants at May 31, 2020	1,625,215	199.73
Granted	274,843	352.68
Forfeited	(48,586)	241.95
Vested	(610,249)	147.32
Outstanding, unvested grants at May 31, 2021	1,241,223	$	264.63