We recognize compensation expense of all employee and non-employee director share-based compensation awards in the consolidated financial statements based upon the grant-date fair value of the awards over the requisite service or vesting period, less any expense incurred for estimated forfeitures. As of December 31, 2020, we have 2.7 million maximum shares available that can be issued as options, stock appreciation rights, and other share-based awards. Shares of our common stock delivered upon exercise or vesting may consist of newly issued shares of our common stock or shares acquired in the open market.

Share-based compensation expense is recognized in the “Selling, general, and administrative expense” line in the Consolidated Statements of Operations and Comprehensive Income (Loss) except for $0.8 million, $0.4 million, and $0.2 million attributable to discontinued operations for the twelve months ended December 31, 2020, 2019, and 2018, respectively. The following table lists the components of share-based compensation expense by type of award.


	Year Ended December 31,
	2020		2019		2018
Stock options	$	741	$	881	$	678
Restricted stock	3,473		1,897		1,630
Performance share units	755		1,155		2,076
Change in estimate of share-based award vesting (1)	(743)		(1,111)		(1,968)
Share-based compensation expense	$	4,226	$	2,822	$	2,416

Unrecognized compensation cost related to unvested awards was $3.6 million as of December 31, 2020. We expect that cost to be recognized over a weighted-average period of 2.2 years.

Option awards are typically granted to key employees on an annual basis. A single option grant is typically awarded to eligible employees each year by the Compensation Committee of the Board of Directors. The Compensation Committee occasionally awards additional individual grants to eligible employees. All employees are awarded options at an exercise price equal to the closing price of our stock on the date of grant. The term life of options is generally ten years with a vesting period of generally three years.

During the years ended 2020, 2019, and 2018, we granted options to purchase 158,700, 210,400, and 57,800 shares, respectively, to certain key employees. The weighted average grant-date fair value of the options granted during 2020, 2019, and 2018 was $4.76, $2.77, and $10.60 per share, respectively. The fair value of our options cannot be determined by market


	2020		2019		2018
Expected term	6 years		6 years		6 years
Average risk-free interest rate	1.42	%	2.47	%	2.66	%
Expected dividend yield	—	%	3.53	%	1.15	%
Expected volatility	52.80	%	49.53	%	47.69	%
Expected forfeiture rate	—	%	4.00	%	4.00	%

The expected term is derived from using the simplified method of determining stock option terms as described under the SAB Topic 14, Share-based payment. The simplified method was used because sufficient historical stock option exercise experience was not available, primarily due to the transformation of the management structure over the past several years.

The average risk-free interest rate is derived from United States Department of Treasury published interest rates of daily yield curves for the same time period as the expected term.

The expected dividend yield is derived by a mathematical formula which uses the expected annual dividends over the expected term divided by the fair market value of our common stock at the grant date. The expected dividend yield for 2020 grants reflects no expected annual dividends over the expected term because we discontinued dividends in 2019.

The expected volatility rate is derived from our actual common stock historical volatility over the same time period as the expected term. The expected volatility rate is derived by a mathematical formula utilizing daily closing price data.

The expected forfeiture rate is determined from examining the historical pre-vesting forfeiture patterns of past option issuances to key employees. While the expected forfeiture rate is not an input of the Black Scholes financial pricing model for determining the fair value of the options, it is an important determinant of stock option compensation expense to be recorded.


	Number of Options (in thousands)	Weighted- Average Exercise Price (per share)		Weighted- Average Remaining Contractual Term (years)	Aggregate Intrinsic Value
Outstanding at January 1, 2020	775	$	13.24
Granted	159	9.44

Forfeited or expired	(63)	15.09
Outstanding at December 31, 2020	871	$	12.41	4.0 years	$	—	(1)
Exercisable at December 31, 2020	682	$	13.17	2.7 years	$	—	(1)

(1)The aggregate intrinsic value is the sum of intrinsic values for each exercisable individual option grant. The intrinsic value is the amount by which the closing market price of our stock at December 31, 2020, was greater than the exercise price of any individual option grant.

No options were exercised during the year ended December 31, 2020. Cash proceeds from the exercise of options in the years ended December 31, 2019 and 2018, totaled less than $0.1 million and $0.3 million, respectively. The tax benefit recognized from stock option exercises was less than $0.1 million and $0.1 million in the years ended December 31, 2019 and 2018, respectively. For the years ended December 31, 2019 and 2018, proceeds from stock options are presented exclusive of tax benefits in cash flows from financing activities in the Consolidated Statements of Cash Flows. The total intrinsic value of options exercised during the years ended December 31, 2019 and 2018, was $7.0 thousand and $0.5 million, respectively.

During the years ended December 31, 2020, 2019, and 2018, we granted 460,255, 339,498, and 86,516 shares of restricted stock to non-executive directors, officers, and certain other key employees. The shares of restricted stock granted during the years ended December 31, 2020, 2019, and 2018, vest pro-rata generally over three years for officers and certain other key employees and over one year for non-executive directors and certain key employees. We determined the fair value of the shares awarded by using the closing price of our common stock as of the date of grant. The weighted average grant-date fair value of

restricted stock granted in the years ended December 31, 2020, 2019, and 2018, was $9.35, $7.74, and $24.55 per share, respectively. The total grant-date fair value of restricted stock that vested in the years ended December 31, 2020, 2019, and 2018, was $1.9 million, $2.9 million, and $1.8 million, respectively.


	Nonvested Restricted Shares (in thousands)	Weighted Average Grant-Date Fair Value (per share)
Unvested at January 1, 2020	222	$	9.33
Granted	460	9.35
Vested	(254)	7.31
Forfeited	(43)	9.17
Unvested at December 31, 2020	385	$	9.42

Performance Share Units (“PSUs”) are a form of long-term incentive compensation awarded to executive officers and certain other key employees designed to directly align the interests of employees to the interests of our stockholders, and to create long-term stockholder value. PSUs granted in 2020 were made pursuant to the NN, Inc. 2019 Omnibus Incentive Plan and a Performance Share Unit Agreement (the “2019 Omnibus Agreement”). PSUs granted in 2019 and 2018 were made pursuant to the NN, Inc. 2016 Omnibus Incentive Plan and a Performance Share Unit Agreement (the “2016 Omnibus Agreement”). Some PSUs are based on total shareholder return (“TSR Awards”), and other PSUs are based on return on invested capital (“ROIC Awards”).

The TSR Awards vest, if at all, upon our achieving a specified relative total shareholder return, which will be measured against the total shareholder return of the S&P SmallCap 600 Index during specified performance periods as defined in the 2019 Omnibus Agreement and the 2016 Omnibus Agreement. The ROIC Awards will vest, if at all, upon our achieving a specified average return on invested capital during the performance periods. Each performance period generally begins on January 1 of the year of grant and ends 36 months later on December 31.

We recognize compensation expense over the performance period in which the performance and market conditions are measured. If the PSUs do not vest at the end of the performance periods, then the PSUs will expire automatically. Upon vesting, the PSUs will be settled by the issuance of shares of our common stock, subject to the award recipient’s continued employment. The actual number of shares of common stock to be issued to each award recipient at the end of the performance periods will be interpolated between a threshold and maximum payout amount based on actual performance results. No dividends will be paid on outstanding PSUs during the performance period; however, dividend equivalents will be paid based on the number of shares of common stock that are ultimately earned at the end of the performance periods.

With respect to the TSR Awards, a participant will earn 50% of the target number of PSUs for “Threshold Performance,” 100% of the target number of PSUs for “Target Performance,” and 150% of the target number of PSUs for “Maximum Performance.” With respect to the ROIC Awards, a participant will earn 35% of the target number of PSUs for “Threshold Performance,” 100% of the target number of PSUs for “Target Performance,” and 150% of the target number of PSUs for “Maximum Performance.” For performance levels falling between the values shown below, the percentages will be determined by interpolation.

TSR Awards:

Threshold Performance
(50% of Shares)

Target Performance
(100% of Shares)

Maximum Performance
(150% of Shares)

2020 grants

th Percentile

2019 grants

th Percentile

2018 grants

th Percentile


ROIC Awards:	Threshold Performance (35% of Shares)		Target Performance (100% of Shares)		Maximum Performance (150% of Shares)
2020 grants (1)	4.9	%	5.1	%	5.6	%
2019 grants	4.7	%	5.8	%	7.0	%
2018 grants	15.5	%	18.0	%	19.5	%

(1)The performance levels for 2020 grants were modified by the compensation committee of the board of directors in the first quarter of 2021 to adjust for the sale of the Life Sciences business and the ongoing effects of the COVID-19 pandemic. Threshold Performance was changed to 6.7% to earn 50% of Shares, Target Performance was changed to 7.9% to earn 100% of Shares, and Maximum Performance was changed to 8.7% to earn 150% of Shares.

We estimate the grant-date fair value of TSR Awards using the Monte Carlo simulation model, as the total shareholder return metric is considered a market condition under ASC Topic 718, Compensation – stock compensation. The grant-date fair value of ROIC Awards is based on the closing price of a share of our common stock on the date of grant.


	TSR Awards			ROIC Awards
Award Year	Shares (in thousands)	Grant-Date Fair Value (per share)		Shares (in thousands)	Grant-Date Fair Value (per share)
2020	139	$	10.88	157	$	9.44
2019	136	$	9.28	174	$	7.93
2018	55	$	24.65	55	$	24.55

We recognize expense for ROIC Awards based on the probable outcome of the associated performance condition. We generally recognize an expense for ROIC Awards based on the Target Performance threshold of 100% because, at the date of grant, the Target Performance is the probable level of performance achievement.


	Nonvested TSR Awards			Nonvested ROIC Awards
	Number of Shares (in thousands)	Weighted Average Grant-Date Fair Value		Number of Shares (in thousands)	Weighted Average Grant-Date Fair Value
Nonvested at January 1, 2020	65	$	13.27	79	$	11.50
Granted	139	10.88		157	9.44
Forfeited	(56)	11.89		(66)	10.32
Expired	(10)	24.65		(10)	24.55
Nonvested at December 31, 2020	138	$	10.58	160	$	9.13

None of the PSUs that were granted in 2016, 2017, and 2018 vested in 2018, 2019, and 2020, respectively, because the actual performance achieved was below the “Threshold Performance” level as defined by the grant agreements.

During the year ended December 31, 2020, we recognized a decrease in share-based compensation expense in continuing operations of $0.3 million in the “Selling, general, and administrative expense” line of the Consolidated Statements of Operations and Comprehensive Income (Loss) to reverse cumulative expense for option, restricted stock, and PSU awards that

were forfeited upon termination of employment and for ROIC Awards that were granted in 2019 and are not expected to achieve Threshold Performance. In 2020 we also recognized a decrease in share-based compensation expense of $0.5 million in the “Income (loss) from discontinued operations, net of tax” line in the Consolidated Statements of Operations and Comprehensive Income (Loss) to reverse cumulative expense for option, restricted stock, and PSU awards that were forfeited upon termination of employees related to the Life Sciences business.

During the year ended December 31, 2019, we recognized a decrease in share-based compensation expense in continuing operations of $1.1 million in the “Selling, general, and administrative expense” line in the Consolidated Statements of Operations and Comprehensive Income (Loss) to reverse cumulative expense for option, restricted stock, and PSU awards that were forfeited upon termination of employment.

During the year ended December 31, 2018, we determined that the probability of performance achievement for ROIC Awards that were granted in 2016, 2017, and 2018 diminished to below the “Threshold Performance” level as defined by the grant agreements, and we recognized a decrease in share-based compensation expense in continuing operations of $1.8 million in “Selling, general, and administrative expense” and $0.2 million in “Income (loss) from discontinued operations, net of tax” on the Consolidated Statements of Operations and Comprehensive Income (Loss).