During the years ended December 31, 2021, 2020 and 2019, we recognized $14.9 million, $15.1 million and $15.7 million, respectively, in stock-based compensation expense, which was allocated between costs of goods sold and selling, general and administrative expenses on the consolidated statements of operations. We recognized tax benefits on stock-based compensation of $1.5 million, $2.4 million and $0.3 million for the years ended December 31, 2021, 2020 and 2019, respectively.

In 2013, Axalta's Board of Directors approved the Axalta Coating Systems Ltd. 2013 Incentive Award Plan (the "2013 Plan") which reserved shares of common stock of the Company for issuance to employees, directors and consultants. The 2013 Plan provided for the issuance of stock options, restricted stock or other stock-based awards. No further awards may be granted pursuant to the 2013 Plan.

In 2014, Axalta's Board of Directors approved the Axalta Coating Systems Ltd. 2014 Incentive Award Plan, as amended and restated (the "2014 Plan"), which reserved additional shares of common stock of the Company for issuance to employees, directors and consultants. The 2014 Plan provides for the issuance of stock options, restricted stock or other stock-based awards. All awards granted pursuant to the 2014 Plan must be authorized by the Board of Directors of Axalta or a designated committee thereof. Our Board of Directors has generally delegated responsibility for administering the 2014 Plan to our Compensation Committee.

The terms of the stock options may vary with each grant and are determined by the Compensation Committee within the guidelines of the 2013 and 2014 Plans. Option life cannot exceed ten years and the Company may settle option exercises by issuing new shares, treasury shares or shares purchased on the open market.

During 2021, we granted restricted stock units and performance share units to certain employees and directors. All awards were granted under the 2014 Plan. The performance share units are subject to certain performance and market conditions, in addition to the service-based vesting conditions. During 2021, the Company withheld shares and used cash to settle certain employees' tax obligation resulting from the vesting of awards in the amount of $1.5 million.

The Black-Scholes option pricing model was used to estimate fair values of the options as of the date of the grant. There were no options granted during 2020 or 2021. The weighted average fair value of options granted in 2019 was $6.98 per share. A majority of these awards vest ratably over three years. Principal weighted average assumptions used in applying the Black-Scholes model were as follows:

The expected term assumptions used for the grants mentioned in the above table were determined using the simplified method. We do not anticipate paying cash dividends in the foreseeable future and, therefore, use an expected dividend yield of zero. Volatility for outstanding grants was based upon our industry peer group since we have a limited history as a public company. The discount rate was derived from the U.S. Treasury yield curve.


Stock Options	Awards (in millions)	Weighted- Average Exercise Price		Aggregate Intrinsic Value (in millions)		Weighted Average Remaining Contractual Life (years)
Outstanding at January 1, 2021	2.5	$	27.34
Granted	—	$	—
Exercised	(0.6)	$	27.12
Forfeited	(0.5)	$	30.55
Outstanding at December 31, 2021	1.4	$	26.30
Vested and expected to vest at December 31, 2021	1.4	$	26.30	$	9.5	5.2
Exercisable at December 31, 2021	1.2	$	26.23	$	8.5	5.0

Cash received by the Company upon exercise of options in 2021 was $15.9 million. Tax shortfall expenses on these exercises were $0.4 million. For the years ended December 31, 2021, 2020 and 2019, the intrinsic value of options exercised was $2.5 million, $4.3 million and $56.6 million, respectively.

At December 31, 2021, there was $0.1 million of unrecognized expense relating to unvested stock options that is expected to be amortized over the weighted average period of 0.3 years.


Restricted Stock Awards and Restricted Stock Units (1)	Awards/Units (in millions)	Weighted-Average Fair Value
Outstanding at January 1, 2021	1.0	$	28.84
Granted	0.7	$	28.95
Vested	(0.5)	$	28.99
Forfeited	(0.1)	$	28.58
Outstanding at December 31, 2021	1.1	$	28.85

At December 31, 2021, there was $12.9 million of unamortized expense relating to unvested restricted stock units that is expected to be amortized over a weighted average period of 1.6 years.

The intrinsic value of awards vested during 2021, 2020 and 2019 was $13.5 million, $14.7 million and $19.7 million, respectively. The total fair value of awards vested during 2021, 2020 and 2019 was $13.6 million, $15.8 million and $20.9 million, respectively. No excess tax benefits or shortfall expenses were recorded related to these exercises.

During the years ended December 31, 2021, 2020 and 2019, the Company granted performance share units ("PSUs") to certain employees of the Company as part of their annual equity compensation award. During the years prior to December 31, 2019, the Company granted performance share awards and performance share units (collectively referred to as "PSAs").

PSUs granted in 2019, 2020 and 2021 are subject to the same service conditions, but also include performance conditions related to internal profitability and return on invested capital metrics over a cumulative performance period of three years, as well as three individual one-year performance periods. At the end of the three-year performance period, the number of PSUs earned based on performance relative to the profitability and invested capital metrics are subject to a market condition in the form of a positive or negative total shareholder return modifier relative to the S&P 500 for 2019 grants and the S&P 400 Materials Index for 2020 and 2021 grants, over the same three-year performance period. The actual number of shares awarded will be between zero and 200% of the target award amount.


Performance Stock Awards and Performance Share Units (1)	Awards (in millions)	Weighted-Average Fair Value
Outstanding at January 1, 2021	0.5	$	31.07
Granted	0.4	$	29.53
Vested	—	$	—
Forfeited	(0.1)	$	31.79
Outstanding at December 31, 2021	0.8	$	30.10

Our performance stock awards and performance share units allow for participants to vest in more or less than the targeted number of shares granted. All of our performance awards are currently performing below the applicable targets. We currently expect a total of 0.2 million shares with a weighted average fair value per share of $29.61 to vest at the respective vesting dates for such awards. At December 31, 2021, there was $4.1 million of unamortized expense relating to unvested performance share units that is expected to be amortized over a weighted average period of 2.1 years. The forfeitures include performance share units that vested below threshold payout.