We have equity-based compensation plans that authorize the issuance of equity-based awards for shares of Class A and Class B common stock to directors, officers and key employees. Equity-based compensation grants are designed to reward long-term contributions to Moog and provide incentives for recipients to remain with Moog.

We have an Employee Stock Purchase Plan ("ESPP") that allows for qualified employees (as defined in the plan) to purchase our common stock at a price equal to 85% of the fair market value at the lower of the beginning or the end of the semi-annual offering period. During 2019, we issued 79,928 shares of Class B common stock at a weighted average price per share of $65.91. During 2018, we issued 53,587 shares of Class B common stock at a weighted average price per share of $65.55.

The 2014 Long Term Incentive Plan ("2014 Plan") authorizes the issuance of a total of 2,000,000 shares of either Class A or Class B common stock. The 2014 Plan is intended to provide a flexible framework that permits the development and implementation of a variety of equity-based programs that base awards on key performance metrics as well as align our long term incentive compensation with our peers and shareholder interests.

During 2019, we granted awards in the form of stock appreciations rights (SARs), performance-based restricted stock units (PSUs) and restricted stock awards (RSAs). The compensation cost for employee and non-employee director equity-based compensation programs for all current and prior year awards granted are as follows:



	2019		2018		2017
Stock appreciation rights	$	2,594	$	2,617	$	3,045
Performance-based restricted stock units	2,048		1,650		978
Restricted stock awards	480		480		480
Employee stock purchase plan	1,342		1,057		74
Stock options	—		—		5
Total compensation cost before income taxes	$	6,464	$	5,804	$	4,582
Income tax benefit	$	1,024	$	1,136	$	1,567

The fair value of SARs granted was estimated on the date of grant using the Black-Scholes option-pricing model. The following table provides the range of assumptions used to value awards and the weighted-average fair value of the awards granted.



	2019			2018			2017
Expected volatility	26%			25% - 26%			27% - 29%
Risk-free rate	3.0		%	2.1%			1.7% - 1.8%
Expected dividends	1.2		%	—		%	—		%
Expected term	5-6 years			5-6 years			5-6 years
Weighted-average fair value of awards granted	$	20.79		$	23.03		$	21.20

To determine expected volatility, we generally use historical volatility based on daily closing prices of our Class A and Class B common stock over periods that correlate with the expected terms of the awards granted. The risk-free rate is based on the United States Treasury yield curve at the time of grant for the appropriate expected term of the awards granted. Expected dividends are based on our history and expectation of dividend payouts. The expected term of equity-based awards is based on vesting schedules, expected exercise patterns and contractual terms.

The number of shares received upon the exercise of a SAR is equal in value to the difference between the fair market value of the common stock on the exercise date and the exercise price of the SAR. The term of a SAR may not exceed ten years from the grant date. The exercise price of SARs and options, determined by a committee of the Board of Directors, may not be less than the fair value of the common stock on the grant date.

SARs and options are as follows:



Stock Appreciation Rights	Number of Awards		Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value
Outstanding at September 29, 2018	1,062,769		$	57.56
Granted in 2019	140,395		80.19
Exercised in 2019	(248,861	)	49.73
Forfeited in 2019	(19,147	)	79.21
Outstanding at September 28, 2019	935,156		$	62.60	5.5 years	$	20,069
Exercisable at September 28, 2019	687,935		$	56.58	4.4 years	$	18,273

The aggregate intrinsic value in the preceding tables represents the total pre-tax intrinsic value, based on our closing price of Class A common stock of $81.71 and Class B common stock of $86.60 as of September 28, 2019. That value would have been effectively received by the SAR holders had all SARs been exercised as of that date.

The intrinsic value of awards exercised and fair value of awards vested are as follows:



	2019		2018		2017
Stock Appreciation Rights
Intrinsic value of SARs exercised	$	10,616	$	7,268	$	13,363
Total fair value of SARs vested	$	2,871	$	3,282	$	4,044
Stock Options
Intrinsic value of options exercised	$	—	$	932	$	2,835
Total fair value of options vested	$	—	$	51	$	66

As of September 28, 2019, total unvested compensation expense associated with SARs amounted to $2,832 and will be recognized over a weighted-average period of two years.

PSU awards consist of shares of our stock which are payable upon the determination that we achieve certain established performance targets and can range from 0% to 200% of the targeted payout based on the actual results. PSU's granted in 2019 have a performance period of three years. The fair value of each PSU granted is equal to the fair market value of our common stock on the date of grant. PSUs granted generally have a three year period cliff vesting schedule; however, according to the grant agreements, if certain conditions are met, the employee (or beneficiary) will receive a prorated amount of the award based on active employment during the service period.

PSUs are as follows:



Performance-Based Restricted Stock Units	Number of Awards		Weighted- Average Grant Date Fair Value
Nonvested at September 29, 2018	67,986		$	76.88
Granted in 2019	36,415		80.19
Vested in 2019	(31,601	)	71.65
Forfeited in 2019	(7,781	)	77.50
Nonvested at September 28, 2019	65,019		$	81.20

As of September 28, 2019, total unvested compensation expense associated with nonvested PSUs amounted to $2,798 and will be recognized over a weighted-average period of two years.

The number of Class B common stock to be issued for PSU awards granted in 2017 that vested based on the achievement of performance targets in 2019, will be approximately 28,700 shares.

The fair value of each RSA granted is equal to the fair market value of our common stock on the date of grant. These shares vest and are issued upon grant. There were 5,988 RSAs granted and vested in 2019 at a price of $80.19 resulting in a fair value of the RSAs vested of $480.

The Management Short Term Incentive Plan ("STI") is intended to attract, motivate and retain highly qualified executives serving on the management team and reward them according to our financial performance with a payment of either cash and/or shares of our common stock. There were 42,795 STI awards granted and vested in 2019 at a price of $84.00, resulting in a fair value of $3,595 in satisfaction of a portion of the 2018 management profit share expense.