The following table summarizes the status of, and changes in, our stock options during the three months ended March 31, 2025.


	Options	Weighted- average exercise price
Outstanding at December 31, 2024	661,377	$	73.76
Exercised	(314,509)	$	78.11
Expired	(1,560)	$	79.71
Outstanding and exercisable at March 31, 2025	345,308	$	69.77

The following table summarizes the status of, and changes in, our nonvested restricted stock units during the three months ended March 31, 2025.


	Restricted stock units	Weighted-average fair value
Nonvested at December 31, 2024	6,001,579	$	124.73
Time-based grants	7,544	$	114.78


Vested	(7,554)	$	127.26
Forfeited	(39,170)	$	134.92
Nonvested at March 31, 2025	5,962,399	$	124.65

Nonvested at March 31, 2025 includes performance-based restricted stock units of 359,941. These nonvested performance-based restricted stock units include 102,345 units for which the performance period has lapsed, and the performance threshold has been met.

The following table presents the compensation expense to be recognized over the remaining vesting periods of the stock-based awards outstanding at March 31, 2025. Estimated future compensation expense will change to reflect future grants of restricted stock awards and units, future option grants, changes in the probability of performance thresholds being met, and adjustments for actual forfeitures.


(in millions)

Second quarter 2025	$	51.8
Third quarter 2025	51.2
Fourth quarter 2025	44.5
2026	100.0
2027 through 2030	67.1
Total	$	314.6

Below is a roll forward of the restricted fund units liability which is reported in deferred compensation liabilities on the consolidated balance sheet.


(in millions)	3/31/2025
Balance at beginning of year	$	14.7
Amortization of grant date value	11.8
Amortization of market appreciation (depreciation)	(0.5)


Balance at end of year	$	26.0

The following table presents the compensation expense to be recognized over the remaining vesting periods of the restricted fund units outstanding at March 31, 2025. Estimated future compensation expense will change to reflect future grants, changes in the market value of the restricted fund units which is based on selected hypothetical investments, and adjustments for actual forfeitures. The grants outstanding will vest by 2029.


(in millions)

Second quarter 2025	$	11.0
Third quarter 2025	10.9
Fourth quarter 2025	8.9
2026	22.3
2027 through 2029	21.0
Total	$	74.1