The Company administers a long-term incentive compensation plan, the Amended and Restated 2015 Omnibus Incentive Plan (the “Plan”), that permits the Company to grant to employees and directors various forms of incentive compensation. The principal purposes of this plan are to focus directors, officers and other employees and consultants on business performance that creates shareholder value, to encourage innovative approaches to the business of the Company, and to encourage ownership of the Company’s stock. The Plan authorizes 7,500,000 common share equivalents available for grant, where grants of full value awards (e.g., shares of restricted stock, restricted stock units and performance stock units) count as one share equivalent. The number of remaining share equivalents available for future issuance under the Plan was 6,406,988 at March 31, 2019.

In the first quarter of 2019, the Company granted 645,346 shares of restricted stock units pursuant to and subject to the provisions of the Plan. Of the units granted, 415,940 will vest in twelve quarterly installments ending in the first quarter of 2022 and 57,521 shares will cliff-vest in first quarter of 2022. The remaining grants specify a stated target number of units, the determination of the actual settlement in shares will be based in part on the achievement of certain financial performance measures of the Company over the three years ended December 31, 2021. For half of the units granted, these performance conditions will determine the actual units vesting in the first quarter 2022 and can be in the range of twenty-five percent to two times the units granted. The remaining half of the restricted stock units vest equally in the first quarter of each of the next three years. These grants include rights as a shareholder in the form of dividend equivalents. Dividend equivalents for time vested restricted stock units will be paid on each dividend payment date for the Company; dividend equivalents for the performance vesting restricted stock will be accrued and paid on the vested number of shares once the performance is achieved and the shares are issued. The fair value of the restricted stock units were estimated based upon the fair value of the underlying shares on the date of the grant.

The Company recorded $0.9 million and $0.4 million of equity-based compensation expense for the outstanding restricted stock units for the three months ended March 31, 2019 and 2018, respectively. The remaining expense related to unvested restricted stock units is $15.1 million as of March 31, 2019 and will be recognized over the next 24 to 30 months.

The following table summarizes the activity related to restricted stock unit awards for the three months ended March 31, 2019 and 2018:

	For the Three Months Ended March 31,
	2019					2018
	Number of Shares			Fair Value per Unit at Award Date		Number of Shares		Fair Value per Unit at Award Date
Non-vested at beginning of period		273,354		$	26.49		672,750	$	5.14
Vested during the period		(44,501	)		26.50		—		—
Forfeited during the period		(29,845	)		19.76		—		—
Granted during the period		645,346			17.87		—		—
Non-vested at end of period		844,354		$	20.14		672,750	$	5.14

During the three months ended March 31, 2019, Cadence granted stock options to certain executive officers. The options were granted at an exercise price equal to a 15% premium to the fair value of the common stock at the date of grant. The options vest over a three-year period and expire at the end of seven years. The remaining expense related to nonvested stock option grants is $3.5 million at March 31, 2019 and will be recognized over the next 33 months.

The following table summarizes the activity related to stock option awards for the three months ended March 31, 2019:

	For the Three Months Ended March 31, 2019
	Number of Shares		Weighted Average Exercise Price
Outstanding options at beginning of period		—	$	-
Granted during the period		1,602,848		20.43
Exercised during the period		—		—
Forfeited or expired during the period		—		—
Non-vested at end of period		1,602,848	$	20.43

The Company uses the Black-Scholes option pricing model to estimate the fair value of the stock options. The following weighted-average assumptions were used for option awards issued during the three months ended March 31, 2019:

	For the Three Months Ended March 31, 2019
Expected dividends		3.1	%
Expected volatility		25.2	%
Risk-free interest rate		2.5	%
Expected term (in years)		4.5
Weighted-average grant date fair value	$	2.32