We issue RSAs and RSUs to participants in our equity plans in the form of time-based RSA’s and RSU’s and performance-based RSA’s and RSU’s.

Compensation cost related to RSA and RSU grants was $1.8 million and $1.4 million for the three months ended September 24, 2022 and September 25, 2021, respectively, and $5.1 million and $4.5 million for the nine months ended September 24, 2022 and September 25, 2021, respectively, and was included in selling, general and administrative expense in the Condensed Consolidated Statements of Operations.

The following table summarizes our RSA and RSU activity for the nine months ended September 24, 2022:

	Shares			Weighted Average Fair Value
Balance at December 25, 2021		206,677		$	85.97
Granted		100,517		$	100.66
Vested		(53,569	)	$	83.49
Canceled		(40,002	)	$	83.51
Balance at September 24, 2022		213,623		$	93.97

For the nine months ended September 24, 2022, we granted 23,995 performance-based RSUs with a grant date fair value of $111.31 per share. For the nine months ended September 25, 2021, we granted 17,714 performance-based RSUs with a grant date fair value of $131.02 per share.

As of September 24, 2022, there was $13.2 million of unrecognized compensation cost related to unvested RSA and RSU grants that is expected to be recognized over a weighted average period of 2.2 years.

We grant stock options to participants in our equity plans. The compensation cost charged against income was $0.5 million and $0.3 million for the three months ended September 24, 2022 and September 25, 2021, respectively, and $1.3 million and $0.9 million for the nine months ended September 24, 2022 and September 25, 2021, respectively, and was included as selling, general and administrative expense in the Condensed Consolidated Statements of Operations.

The following table summarizes our stock option activity for the nine months ended September 24, 2022:

	Shares			Weighted Average Exercise Price		Weighted Average Remaining Term (In years)		Aggregate Intrinsic Value
Balance at December 25, 2021		233,396		$	77.85
Granted		78,574		$	97.16
Canceled		(11,236	)	$	77.45
Expired		(663	)	$	101.45
Exercised		(31,141	)	$	71.78
Balance at September 24, 2022		268,930		$	84.16		5.6	$	1,793,436
Exercisable at September 24, 2022		95,927		$	76.08		4.2	$	929,436

As of September 24, 2022, there was $3.4 million of unrecognized compensation cost related to unvested stock options that is expected to be recognized over a weighted average period of 2.9 years.

During the nine months ended September 24, 2022 and September 25, 2021, we purchased 13,327 shares and 31,462 shares, respectively, under the ESPP. Compensation cost related to the ESPP was $0.2 million and $0.0 million for the three months ended September 24, 2022 and September 25, 2021, respectively, and $0.3 million and $0.7 million for the nine months ended September 24, 2022 and September 25, 2021, respectively.