In May 2007, the Manhattan Associates, Inc. 2007 Stock Incentive Plan (the “2007 Plan”) was approved by our shareholders and subsequently amended in May 2009 and May 2011. The amended 2007 Plan provides for the grant of stock options, restricted stock, restricted stock units, and stock appreciation rights. Vesting conditions can be service-based or performance-based, or a combination of both.

As amended, a maximum of 30,000,000 shares are available for grant under the amended 2007 Plan. Each stock option or stock appreciation right granted is counted against the maximum share limitation as one share, and each share of restricted stock or restricted stock unit granted (including those that are service based or performance based) counts against the maximum share limitation as two shares. Options and stock appreciation rights cannot have a term exceeding seven years. As of December 31, 2019, there were 8,073,256 shares available for issuance under the amended 2007 Plan. The amended 2007 Plan is administered by the Compensation Committee of the Board of Directors. The committee has the authority to interpret the provisions thereof.

The restricted stock awards contain vesting provisions that are 50% service based and 50% performance based for employee awards and 100% service based for non-employee members of the Board of Directors (“Outside Directors”). The employee awards have a four year vesting period, with the performance portion tied to annual revenue and earnings per share targets. The awards to Outside Directors have a one year vesting period. We recognize compensation cost for service-based restricted awards with graded vesting on a straight-line basis over the entire vesting period, with the amount of compensation cost recognized at any date at least equal to the portion of the grant-date value of the award that is vested at that date. For our performance-based restricted stock awards with graded vesting, we recognize compensation cost on an accelerated basis applying straight-line expensing for each separately vesting portion of each award.

In January 2012, in order to simplify equity grant administration, we changed the practice of granting restricted stock in favor of granting restricted stock units, or RSUs, which convert to our common stock upon vesting. There is no material difference between the grant of restricted stock and the grant of RSUs to either us or the recipients receiving the grants; however, in contrast to the granting of restricted stock, no stock will actually be issued under the granting of RSUs until the units vest. Currently, we do not grant stock options.

We present below a summary of changes in unvested units of restricted stock during 2019:

	Number of Units	Grant Date Fair Value
Outstanding at January 1, 2019	997,173	$52.22
Granted	945,159	49.48
Vested	(386,060)	51.79
Forfeited	(59,579)	50.56
Outstanding at December 31, 2019	1,496,693	$50.67

The Company recorded equity-based compensation expense related to restricted stock and RSUs (collectively “restricted stock awards”) of $31.8 million, $19.9 million, and $16.2 million in 2019, 2018 and 2017, respectively. The total fair value of restricted stock awards vested in 2019, 2018 and 2017, based on market value at the vesting dates was $18.2 million, $18.1 million, and $18.8 million, respectively. The weighted average grant-date fair value of RSUs granted during fiscal year 2019, 2018 and 2017 was $49.48, $51.72 and $49.01, respectively. As of December 31, 2019, unrecognized compensation cost related to unvested RSU totaled $47.5 million and is expected to be recognized over a weighted average period of approximately 2.5 years. In January 2017, we elected to recognize forfeitures of equity-based payments as they occur.

Included in RSU grants for the year ended December 31, 2019 are 282,327 units that have performance-based vesting criteria. The performance criteria are tied to our financial performance. As of December 31, 2019, the associated equity-based compensation expense has been recognized for the portion of the award attributable to the 2019 performance criteria.