
	For the Three Months Ended September 30,		For the Nine Months Ended September 30,
	2023	2024	2023	2024
Share-based compensation expense	$14.5	$10.2	$43.9	$42.1
Tax benefit	1.9	1.2	5.5	5.2

As of December 31, 2023, the Company had unrecognized share-based compensation expense of $54.4 million. As of

September 30, 2024, the Company had unrecognized share-based compensation expense of $48.7 million, which will be

recognized over a weighted average period of approximately two years (assuming no forfeitures).

The following table summarizes transactions in the Company’s restricted stock units:


	Restricted Stock Units	Weighted Average Grant Date Value
Unvested units—December 31, 2023	0.9	$138.51
Units granted	0.2	159.32
Units vested	(0.3)	129.72
Units forfeited	(0.0)	149.00
Performance condition changes	0.0	154.72
Unvested units—September 30, 2024	0.8	147.40

For the nine months ended September 30, 2023 and 2024, the Company granted restricted stock units with fair values of

$49.2 million and $31.3 million, respectively. These restricted stock units were valued based on the closing price of the

Company’s common stock on the grant date and the number of shares expected to vest. Restricted stock units containing

vesting conditions generally require service over a period of three years to four years and may also require the satisfaction of

certain performance conditions. For awards with performance conditions, the number of restricted stock units expected to vest


	Stock Options	Weighted Average Exercise Price	Weighted Average Remaining Contractual Life (Years)
Unexercised options outstanding—December 31, 2023	3.2	$76.74
Options granted	—	—
Options exercised	(1.3)	74.82
Options forfeited	(0.0)	185.98
Options expired	(0.0)	152.36
Performance condition changes	0.0	129.17
Unexercised options outstanding—September 30, 2024	1.9	78.02	2.1
Exercisable at September 30, 2024	1.5	75.89	1.9

The Company did not grant any stock options during the nine months ended September 30, 2023 and 2024. Stock options

generally vest over a period of three years to five years and expire seven years after the grant date. All stock options have been

granted with exercise prices equal to the closing price of the Company’s common stock on the grant date. Substantially all of

the Company’s outstanding stock options contain both service and performance conditions. For awards with performance