STOCK PLANS (Tables)

12 Months Ended

Dec. 31, 2023

STOCK PLANS

Summary of stock option activity

The following table summarizes stock option activity for the year ended December 31, 2023 under all Plans:

		Weighted
		Average
	Number of	Exercise
	Options	Price
Balance at beginning of year	1,117,359	$	93.31
Options granted	102,292		178.15
Options exercised	(299,682)		118.17
Options canceled	(350)		63.08
Options forfeited	—		—
Balance at end of year	919,619		108.85
Exercisable at end of year	671,164		95.20

Weighted average assumptions used for estimating fair value of options granted

	2023			2022			2021
Expected volatility		27.63	%		27.14	%		28.01	%
Dividend yield		1.59	%		1.84	%		2.17	%
Risk-free interest rate		4.04	%		1.94	%		0.55	%
Expected option life (years)		4.8			4.7			4.7
Weighted average fair value per option granted during the year	$	46.94		$	27.42		$	21.70

Summary of nonvested stock options

The following table summarizes non-vested stock options for the year ended December 31, 2023:

		Weighted Average
	Number of	Fair Value at
	Options	Grant Date
Balance at beginning of year	317,006	$	13.93
Granted	102,292		46.94
Vested	(170,493)		21.61
Canceled	(350)		18.34
Forfeited	—		—
Balance at end of year	248,455		28.36

Summary of information about awards outstanding, by exercise price range

The following table summarizes information about awards outstanding as of December 31, 2023:

	Outstanding				Exercisable
		Weighted		Weighted		Weighted		Weighted
	Number of	Average		Average	Number of	Average		Average
	Stock	Exercise		Remaining	Stock	Exercise		Remaining
Exercise Price Range	Options	Price		Life (years)	Options	Price		Life (years)
Under $49.99	—	$	—	—	—	$	—	—
$50.00 - $59.99	18,371		58.17	2.11	18,371		58.17	2.11
Over $60.00	901,248		109.88	6.35	652,793		96.24	5.60
	919,619			6.27	671,164			5.50

Summary of RSU and PSU activity

The following table summarizes RSU and PSU activity for the year ended December 31, 2023 under all Plans:

		Weighted
		Average
	Number of	Grant Date
	Units	Fair Value
Balance at beginning of year	391,072	$	111.90
Units granted	130,831		180.04
Units vested	(177,048)		95.90
Units forfeited	(5,414)		139.14
Balance at end of year	339,441		140.50