In the first quarter of 2023, the Company updated its Long-Term Incentive Program (“LTIP”) to provide employees with an award of stock options and initial grants of restricted stock units (“RSUs”), and made an initial grant of performance share units ("PSUs") to members of the Company's Executive Leadership Team ("ELT"). In connection with this update, the awards are now granted in the first quarter of each year. Prior to 2023, the awards were granted in the second quarter. The Company recognizes the grant-date fair value for each of these awards, less estimated forfeitures, as compensation expense ratably over the vesting period. For employees and directors that meet retirement eligibility requirements, the expense related to share-based compensation is recognized on the date of grant as there is no future service period required for the awards to vest.

The following table provides a summary of option activity:


						Weighted
						Average
				Weighted		Remaining
				Average		Contractual		Aggregate
				Exercise		Term		Intrinsic
	Options			Price (per share)		(in Years)		Value
Outstanding at December 31, 2023		10.2		$	68.77
Granted		1.0			100.43
Exercised		(1.7	)		52.40
Cancelled		(0.1	)		86.15
Outstanding at September 30, 2024		9.4		$	75.03		6.0	$	281.4
Exercisable at September 30, 2024		6.0		$	66.78		4.6	$	226.9

The following table provides information regarding the intrinsic value of stock options exercised and stock compensation expense related to stock option awards:


	Three Months Ended				Nine Months Ended
	September 30,		September 30,		September 30,		September 30,
	2024		2023		2024		2023
Intrinsic Value of Stock Options Exercised	$	5.3	$	14.2	$	86.6	$	121.9
Stock Compensation Expense Related to Stock Option Awards	$	4.3	$	3.8	$	24.8	$	22.7
Issued Stock Options		0.0		0.0		1.0		1.0
Weighted Average Fair Value of Stock Options issued (per share)	$	0.0	$	0.0	$	29.90	$	24.05
Fair Value of Stock Options Issued	$	0.0	$	0.0	$	31.1	$	24.8

The following table provides a summary of the assumptions used in the valuation of issued stock options:


	Three Months Ended		Nine Months Ended
	September 30,	September 30,	September 30,			September 30,
	2024	2023	2024			2023
Risk-free interest rate	N/A	N/A		4.2	%		4.0	%
Expected life in years	N/A	N/A		7.2			7.3
Expected volatility	N/A	N/A		22.3	%		22.4	%
Dividend yield	N/A	N/A		1.1	%		1.3	%

The Company granted employees 105,600 RSUs with a total fair value of $10.8 at a weighted average grant date fair value of $101.93 per RSU during the nine months ended September 30, 2024 and granted employees 119,570 RSUs with a total fair value of $10.3 at a weighted average grant date fair value of $86.18 per RSU during the nine months ended September 30, 2023. The annual RSU grants vest one-third on each of the first, second and third anniversaries of the grant date, subject to the recipient’s continued employment with the Company from the grant date through the applicable vesting date, and are settled with shares of the Company’s Common Stock within 60 days following the applicable vesting date.

Additionally, in connection with the Hero Acquisition (see Note 10), 854,882 shares of restricted stock were issued to certain individuals in October 2022 with a total fair value of $61.5. This restricted stock is recognized as compensation expense ratably over the vesting period if those individuals continue to be employed by the Company. The vesting requirements are satisfied at various dates over a three-year period from the date of the acquisition. 213,719 shares have vested as of September 30,2024 with an additional 213,719 vesting in October 2024. The restricted stock expense associated with the Hero Acquisition for the nine months ended September 30, 2024 and 2023 was $17.2 and $21.9, respectively, and is included in the Non-cash compensation expense caption in the condensed consolidated statement of cash flows.

In the first quarter of 2024 and 2023, the Company granted PSUs to members of the Executive Leadership Team including the CEO, with an aggregate award equal to 19,960 and 19,650 PSUs, respectively. The PSUs were valued at a weighted average grant date fair value per PSU equal to $122.24 in 2024 and $110.95 in 2023 using a Monte Carlo model. The performance target is based on the Company's total shareholder return ("TSR") relative to a Company-selected peer group. The PSUs vest on the later of (i) the third anniversary of the grant date, and (ii) the date that the Board's Compensation & Human Capital Committee certifies the achievement of the applicable performance goals, in each case, subject to the recipient’s continued employment with the Company from the grant date through the vesting date. The number of shares that may be issued ranges from 0% to 200% based on relative TSR during the three-year performance period.