Charter’s stock incentive plan provides for grants of nonqualified stock options, incentive stock options, stock appreciation rights, dividend equivalent rights, performance units and performance shares, share awards, phantom stock, restricted stock units and restricted stock. Directors, officers and other employees of the Company and its subsidiaries, as well as others performing consulting services for the Company, are eligible for grants under the stock incentive plan. The stock incentive plan allows for the issuance of up to 16 million shares of Charter Class A common stock (or units convertible into Charter Class A common stock).

Restricted stock, restricted stock units and stock options are measured at the grant date fair value and amortized to stock compensation expense over the requisite service period. The fair value of stock options is estimated on the date of grant using the Black-Scholes option-pricing model. The grant date weighted average assumptions used during the years ended December 31, 2022, 2021 and 2020 were: risk-free interest rate of 1.7%, 0.7% and 1.4%, respectively; expected lives of 5.7 years, 5.9 years and 5.5 years, respectively; and expected volatility of 28% during the year ended December 31, 2022 and 27% during each of the years ended December 31, 2021 and 2020. The Company’s volatility assumptions represent management’s best estimate and were based on a review of historical and implied volatility. Expected lives were estimated using historical exercise data. The valuations assume no dividends are paid. The Company has elected an accounting policy to assume zero forfeitures for stock awards grants and account for forfeitures when they occur.

Stock options and restricted stock units generally cliff vest three years from the date of grant. Stock options generally expire ten years from the grant date and restricted stock units have no voting rights. Restricted stock generally vests one year from the date of grant.

As of December 31, 2022, total unrecognized compensation remaining to be recognized in future periods totaled $211 million for stock options, $1.0 million for restricted stock and $275 million for restricted stock units and the weighted average period over which they are expected to be recognized is 2 years for stock options, 4 months for restricted stock and 2 years for restricted stock units. The Company recorded $470 million, $430 million and $351 million of stock compensation expense for the years ended December 31, 2022, 2021 and 2020, respectively, which is included in operating costs and expenses.


	Year Ended December 31,
	2022							2021							2020
	Shares			Weighted Average Exercise Price		Aggregate Intrinsic Value		Shares			Weighted Average Exercise Price		Aggregate Intrinsic Value		Shares			Weighted Average Exercise Price		Aggregate Intrinsic Value
Outstanding, beginning of period	8,433			$	362.26			8,842			$	312.95			10,549			$	241.14
Granted	1,469			$	577.64			1,295			$	629.57			1,672			$	536.27
Exercised	(552)			$	295.51	$	133	(1,568)			$	295.46	$	606	(3,160)			$	191.43	$	1,176
Canceled	(170)			$	570.44			(136)			$	476.90			(219)			$	312.94
Outstanding, end of period	9,180			$	396.89	$	468	8,433			$	362.26			8,842			$	312.95

Weighted average remaining contractual life	6		years					6		years					7		years
Options exercisable, end of period	5,320			$	266.78	$	467	4,102			$	237.45			2,940			$	220.78
Options expected to vest, end of period	3,860			$	576.23	$	—
Weighted average fair value of options granted	$	172.24						$	171.21						$	148.02


	Year Ended December 31,
	2022			2021			2020
	Shares	Weighted Average Grant Price		Shares	Weighted Average Grant Price		Shares	Weighted Average Grant Price
Outstanding, beginning of period	5	$	654.33	6	$	504.53	8	$	359.33
Granted	7	$	494.72	5	$	654.33	6	$	504.53
Vested	(5)	$	654.33	(6)	$	504.53	(8)	$	359.33
Canceled	—	$	—	—	$	—	—	$	—
Outstanding, end of period	7	$	494.72	5	$	654.33	6	$	504.53


	Year Ended December 31,
	2022			2021			2020
	Shares	Weighted Average Grant Price		Shares	Weighted Average Grant Price		Shares	Weighted Average Grant Price
Outstanding, beginning of period	1,294	$	449.03	1,651	$	337.82	2,059	$	249.45
Granted	638	$	522.45	367	$	629.47	423	$	509.64
Vested	(592)	$	307.67	(665)	$	269.88	(753)	$	194.40
Canceled	(74)	$	569.11	(59)	$	467.26	(78)	$	317.45
Outstanding, end of period	1,266	$	545.00	1,294	$	449.03	1,651	$	337.82