The Company’s 2017 Long-Term Incentive Plan (“Incentive Plan”) permits the granting of stock options, stock appreciation rights, restricted stock and restricted stock units to its employees and directors for up to 3.3 million shares of common stock, plus an additional 1.7 million shares underlying equity awards issued under the 2007 Long-Term Incentive Plan. The Company may also issue share-based compensation as inducement awards to new employees upon approval of the Board of Directors.

Compensation cost charged to expense related to share-based compensation arrangements was $4,643, $2,917 and $2,651, for the years ended December 31, 2018, 2017 and 2016, respectively.

The NQSO awards were granted with an exercise price equal to the market price of the Company’s common stock at the date of grant. The option awards generally vest in three equal annual installments commencing on the first anniversary of the grant date, and have ten year exercise periods.

The fair value of the NQSOs was determined at the grant date using a Black-Scholes option pricing model, which requires the Company to make several assumptions. The risk-free interest rate is based on the U.S. Treasury yield curve in effect for the expected term of the option at the time of grant. The annual dividend yield on the Company’s common stock is based on estimates of future dividends during the expected term of the NQSOs. The expected life of the NQSOs was determined from historical exercise data providing a reasonable basis upon which to estimate the expected life. The volatility assumptions were based on historical volatility of Great Lakes. There is not an active market for options on the Company’s common stock and, as such, implied volatility for the Company’s stock was not considered. Additionally, the Company’s general policy is to issue new shares of registered common stock to satisfy stock option exercises or grants of restricted stock. No NQSO awards were granted in 2018, 2017 and 2016.

A summary of stock option activity under the Incentive Plan as of December 31, 2018, and changes during the year ended December 31, 2018, is presented below:

Options	Shares			Weighted Average Exercise Price		Weighted-Average Remaining Contract Term (yrs)		Aggregate Intrinsic Value ($000's)
Outstanding as of January 1, 2018		1,377		$	6.34
Granted		—			—
Exercised		(62	)		4.78
Forfeited or Expired		(155	)		5.60
Outstanding as of December 31, 2018		1,160		$	6.52		2.8	$	646

Vested at December 31, 2018		1,160		$	6.52		2.8	$	646

RSUs can either vest in equal portions over the three year vesting period or vest in one installment on the third anniversary of the grant date. The fair value of RSUs was based upon the Company’s stock price on the date of grant. A summary of the status of the Company’s non-vested RSUs as of December 31, 2018, and changes during the year ended December 31, 2018, is presented below:

Nonvested Restricted Stock Units	Shares			Weighted-Average Grant-Date Fair Value
Outstanding as of January 1, 2018		2,196		$	5.06
Granted		2,051			4.83
Vested		(758	)		4.95
Forfeited		(501	)		5.44
Outstanding as of December 31, 2018		2,988		$	4.88

Expected to vest at December 31, 2018		2,084		$	4.63

As of December 31, 2018, there was $4,827 of total unrecognized compensation cost related to non-vested RSUs granted under the Plan. That cost for non-vested RSUs is expected to be recognized over a weighted-average period of 1.9 years.

The Incentive Plan permits the employee to use vested shares from RSUs to satisfy the grantee’s U.S. federal income tax liability resulting from the issuance of the shares through the Company’s retention of that number of common shares having a market value as of the vesting date equal to such tax obligation up to the minimum statutory withholding requirements. The amount related to shares used for such tax withholding obligations was approximately $1,205 and $328 for the years ended December 31, 2018 and 2017, respectively.

The Company uses a combination of cash and share-based compensation to attract and retain qualified candidates to serve on our Board of Directors. Compensation is paid to non-employee directors. Directors who are employees receive no additional compensation for services as members of the Board or any of its committees. Share-based compensation is paid pursuant to the Incentive Plan. Each non-employee director of the Company receives an annual retainer of $155, payable quarterly in arrears, and is generally paid 50% in cash and 50% in common stock or deferred restricted stock units of the Company. Directors may elect to receive some or all of the cash retainer in common stock or deferred restricted stock units. In 2018, the Chairman of the Board received an additional $100 of annual compensation, paid 100% in common stock.

In the years ended December 31, 2018, 2017 and 2016, 156 thousand, 207 thousand and 86 thousand shares, respectively, of the Company’s common stock or restricted stock units were issued to non-employee directors under the Incentive Plan.