Under our employee and non-employee director stock-based compensation plans (the “Plans”), we may grant incentive or non-qualified stock options, restricted common shares and performance shares to employees and non-qualified stock options and restricted common shares to non-employee directors. We classify share-based compensation expense within SG&A expense to correspond with the same financial statement caption as the majority of the cash compensation paid to employees. A total of 2,109,134 of Worthington Industries, Inc. common shares were authorized and available for issuance in connection with the Plans in place at May 31, 2021.

We recognized pre-tax stock-based compensation expense of $19,129,000 ($14,729,000 after-tax), $11,883,000 ($9,150,000 after-tax), and $11,733,000 ($9,034,000 after-tax) under the Plans during fiscal 2021, fiscal 2020 and fiscal 2019, respectively. At May 31, 2021, the total unrecognized compensation cost related to non-vested awards was $17,525,000, which will be expensed over the next three fiscal years.

Stock options may be granted to purchase common shares at not less than 100% of the fair market value of the underlying common shares on the date of the grant. All outstanding stock options are non-qualified stock options. The exercise price of all stock options granted has been set at 100% of the fair market value of the underlying common shares on the date of grant. Generally, stock options granted to employees vest and become exercisable at the rate of (i) 20% per year for options granted before June 30, 2011, and (ii) 33% per year for options granted on or after June 30, 2011, in each case beginning one year from the date of grant, and expire ten years after the date of grant. Non-qualified stock options granted to non-employee directors vest and become exercisable on the earlier of (a) the first anniversary of the date of grant or (b) the date on which the next annual meeting of shareholders of Worthington Industries, Inc. is held following the date of grant for any stock option granted as of the date of an annual meeting of shareholders of Worthington Industries, Inc. Stock options can be exercised through net-settlement, at the election of the option holder.

U.S. GAAP requires that all share-based awards be recorded as expense in the statement of earnings based on their grant-date fair value. We calculate the fair value of our non-qualified stock options using the Black-Scholes option pricing model and certain assumptions. The computation of fair values for all stock options incorporates the following assumptions: expected volatility (based on the historical volatility of Worthington Industries, Inc. common shares); risk-free interest rate (based on the U.S. Treasury strip rate for the expected term of the stock options); expected term (based on historical exercise experience); and dividend yield (based on annualized current dividends and an average quoted price of Worthington Industries, Inc. common shares over the preceding annual period).

The table below sets forth the non-qualified stock options granted during each of the last three fiscal years. For each grant, the exercise price was equal to the closing market price of the underlying common shares at the respective grant date. The fair values of these stock options were based on the Black-Scholes option pricing model, calculated at the respective grant dates. The calculated pre-tax stock-based compensation expense for these stock options, will be recognized on a straight-line basis over the respective vesting periods of the stock options.

The weighted average fair value of stock options granted in fiscal 2021, fiscal 2020 and fiscal 2019 was based on the following weighted average assumptions:

The following tables summarize our stock option activity for the years ended May 31:

	2021					2020					2019
(in thousands, except per share amounts)	Stock Options			Weighted Average Exercise Price		Stock Options			Weighted Average Exercise Price		Stock Options			Weighted Average Exercise Price
Outstanding, beginning of year		1,352		$	27.34		1,555		$	24.01		2,019		$	22.26
Granted		116			36.93		101			38.91		96			42.86
Exercised		(854	)		22.16		(303	)		13.99		(506	)		18.45
Forfeited		(12	)		31.52		(1	)		43.04		(54	)		44.31
Outstanding, end of year		602			36.44		1,352			27.34		1,555			24.01
Exercisable at end of year		389			35.55		1,167			25.34		1,397			21.96

			Weighted
			Average
	Number of		Remaining		Aggregate
	Stock		Contractual		Intrinsic
	Options		Life		Value
	(in thousands)		(in years)		(in thousands)
May 31, 2021
Outstanding		602		5.61	$	18,037
Exercisable		389		4.15	$	12,415

May 31, 2020
Outstanding		1,352		3.21	$	8,846
Exercisable		1,167		2.44	$	8,846

May 31, 2019
Outstanding		1,555		3.15	$	18,728
Exercisable		1,397		2.62	$	18,728

The total intrinsic value of stock options exercised during fiscal 2021 was $14,934,000. The total amount of cash received from the exercise of stock options during fiscal 2021 was $12,102,000, and the related excess tax benefit realized from share-based payment awards was $4,261,000.

The following table summarizes information about non-vested stock option awards for the year ended May 31, 2021:

				Weighted
				Average
	Number of			Grant Date
	Stock Options			Fair Value
	(in thousands)			Per Share
Non-vested, beginning of year		185		$	11.06
Granted		116			10.43
Vested		(76	)		12.50
Forfeited		(12	)		9.58
Non-vested, end of year		213		$	10.29

We have awarded restricted common shares to certain employees and non-employee directors that contain service-based vesting conditions. Service-based restricted common shares granted to employees cliff vest generally three years from the date of grant. Service-based restricted common shares granted to non-employee directors vest under the same parameters as discussed above with respect to non-qualified stock option grants. All service-based restricted common shares are valued at the closing market price of the Worthington Industries, Inc. common shares on the date of the grant.

The table below sets forth the service-based restricted common shares we granted during each of fiscal 2021, fiscal 2020 and fiscal 2019. The calculated pre-tax stock-based compensation expense for these restricted common shares will be recognized on a straight-line basis over their respective service periods.

The following tables summarize the activity for service-based restricted common shares for the years ended May 31:

	2021					2020					2019
(in thousands, except per share amounts)	Restricted Common Shares			Weighted Average Grant Date Fair Value		Restricted Common Shares			Weighted Average Grant Date Fair Value		Restricted Common Shares			Weighted Average Grant Date Fair Value
Outstanding, beginning of year		643		$	41.79		811		$	43.25		796		$	40.80
Granted		307			38.99		247			37.50		339			43.35
Vested		(146	)	43.41			(395	)		42.00		(229	)		34.63
Forfeited		(27	)	42.15			(20	)		44.10		(95	)		43.83
Outstanding, end of year		777			40.36		643			41.79		811			43.25

Weighted average remaining contractual life of
outstanding restricted common shares (in years)		1.33					1.55					1.21

Aggregate intrinsic value of outstanding restricted
common shares	$	51,541				$	19,230				$	27,681

Aggregate intrinsic value of restricted common
shares vested during the year	$	5,873				$	15,322				$	10,388

On June 24, 2014, we granted an aggregate of 50,000 market-based restricted common shares to two key employees under one of the Plans. Vesting of these restricted common share awards was to be contingent upon the price of the Worthington Industries, Inc. common shares reaching $60.00 per share and remaining at or above that price for 30 consecutive days during the five-year period following the date of grant and the completion of a five-year service vesting period. The grant-date fair value of these restricted common shares, as determined by a Monte Carlo simulation model, was $32.06 per share. The following assumptions were used to determine the grant-date fair value and the derived service period for these market-based restricted common shares:

The calculated pre-tax stock-based compensation expense was determined to be $1,603,000. In fiscal 2016, 25,000 of these restricted common shares were forfeited. On September 26, 2018, the remaining market-based restricted common share award was modified to extend the vesting period by one year, to June 24, 2020. The incremental fair value as of the modification date was $261,000 and was recognized on a straight-line basis over the remaining term. The conditions required for vesting of these remaining market-based restricted common shares was not met by June 24, 2020 and they were subsequently forfeited.

On September 28, 2018, we granted an aggregate 225,000 market-based restricted common shares to two key employees under one of the Plans. Vesting of these restricted common share awards is contingent upon the price of our common shares reaching $65.00 per share and remaining at or above that price for 90 consecutive days during the five-year period following the date of grant and the completion of a five-year service vesting period. The grant-date fair value of these restricted common shares, as determined by a Monte Carlo simulation model, was $23.38 per share. The following assumptions were used to determine the grant-date fair value and the derived service period for these restricted common shares:

The calculated pre-tax stock-based compensation expense for these restricted common shares is $5,261,000 and will be recognized on a straight-line basis over the five-year service vesting period, net of any forfeitures.

On September 25, 2019, we granted an aggregate of 50,000 market-based restricted common shares to one key employee under one of the Plans. Vesting of these restricted common share awards is contingent upon the price of our common shares reaching $65.00 per share and remaining at or above that price for 90 consecutive days during the five-year period following the date of grant and the completion of a five-year service vesting period. The grant-date fair value of these restricted common shares, as determined by a Monte Carlo simulation model, was $14.31 per share. The following assumptions were used to determine the grant-date fair value and the derived service period for these restricted common shares:

On June 25, 2020, we granted an aggregate of 45,000 restricted common shares to three key employees under one of the Plans. Vesting of these restricted common share awards is contingent upon the price of our common shares reaching $65.00 per share within a five-year period from the grant and remaining at or above that price for 90 consecutive days and the completion of a three-year service vesting period. The grant date fair value of these restricted common shares, as determined by a Monte Carlo simulation model, was $20.87 per share. The following assumptions were used to determine the grant-date fair value and the derived service period for these restricted common shares:

We have awarded performance shares to certain key employees that are contingent (i.e., vest) based upon the level of achievement with respect to corporate targets for cumulative corporate economic value added, earnings per share growth and, in the case of business unit executives, business unit operating income targets for the three-year periods ended or ending May 31, 2021, 2022 and 2023. These performance share awards will be paid, to the extent earned, in common shares of Worthington Industries, Inc. in the fiscal quarter following the end of the applicable three-year performance period. The fair value of performance shares is determined by the closing market prices of the underlying common shares at their respective grant dates and the pre-tax stock-based compensation expense is based on our periodic assessment of the probability of the targets being achieved and our estimate of the number of common shares that will ultimately be issued.

The table below sets forth the performance shares we granted (at target levels) during fiscal 2021, fiscal 2020 and fiscal 2019: