Unit-Based Compensation

9 Months Ended

Sep. 30, 2020

The Partnership's unit-based awards granted in 2020 and 2019 were valued using the closing price of NRP's units as of the grant date. The grant date fair value of these awards granted during the nine months ended September 30, 2020 and 2019 were $3.5 million and $5.4 million, respectively. Total unit-based compensation expense associated with these awards was $0.9 million and $0.5 million for the three months ended September 30, 2020 and 2019, respectively, and $2.6 million and $1.8 million for the nine months ended September 30, 2020 and 2019, respectively, and is included in general and administrative expenses and operating and maintenance expenses on the Partnership's Consolidated Statements of Comprehensive Income (Loss). The unamortized cost associated with unvested outstanding awards as of September 30, 2020 is $4.4 million, which is to be recognized over a weighted average period of 1.8 years. The unamortized cost associated with unvested outstanding awards as of December 31, 2019 was $3.5 million.

A summary of the unit activity in the outstanding grants during 2020 is as follows:


(In thousands)	Common Units	Weighted Average Exercise Price
Outstanding at January 1, 2020	157	$	37.48
Granted	203	$	17.20
Fully vested and issued	—	$	—
Forfeitures	(5)	$	17.20
Outstanding at September 30, 2020	355	$	26.20