Stock-Based Compensation Plan (Tables)

3 Months Ended

Mar. 31, 2021

Stock-Based Compensation Plan

Schedule of share-based payment award, stock options, valuation assumptions

The Company utilized the Black-Scholes valuation model for estimating the fair value of the stock options granted, with the following weighted-average assumptions for options granted in the three months ended March 31, 2021 and 2020, respectively:

	2021		2020
Risk-free interest rate	1.18	%	0.55	%
Expected volatility	127	%	123	%
Expected term in years	6.1		5.8
Dividend yield	—	%	—	%

Schedule of option activity under stock-based compensation plans

The following summary represents option activity under the Company’s stock-based compensation plans for the three months ended March 31, 2021:

		Weighted-
		Average
		Exercise
	Options	Price
	(in thousands)
Outstanding at December 31, 2020	274	$	20.57
Granted	212		7.02
Outstanding at March 31, 2021	486		14.63
Exercisable at March 31, 2021	92	$	47.36