	March 27, 2020			December 27, 2019
Term loan	$	159,687		$	161,875
Revolving credit facility		24,162			19,162
Total principal amount of long-term debt		183,849			181,037
Less unamortized debt issuance costs		(2,740	)		(2,983	)
Total long-term debt, net		181,109			178,054
Less current portion		(8,750	)		(8,750	)
Total long-term debt, less current portion, net	$	172,359		$	169,304

On February 15, 2018, we amended and restated our credit agreement, which replaced our existing credit facilities with a $175.0 million term loan and a $125.0 million revolving credit facility. The amendment reduced our borrowing rate, depending on our leverage ratio, and extended the maturity date. We incurred debt issuance costs of $2.1 million in connection with the amendment. The amendment did not meet the definition of an extinguishment and was accounted for as a debt modification.

Interest is charged at either the Base Rate or the Eurodollar rate (as such terms are defined in the credit agreement) at our option, plus an applicable margin. The Base Rate is equal to the higher of i) the Prime Rate, ii) the Federal Funds Rate plus 0.5%, or iii) the Eurodollar Rate plus 1.00%. The Eurodollar rate is equal to LIBOR. The applicable margin on Base Rate and Eurodollar Rate loans is 0.75‑1.50% and 1.75‑2.50% per annum, respectively, depending on our leverage ratio. We are also charged a commitment fee of 0.20%-0.35% on the unused portion of our revolving credit facility. Base Rate interest payments and commitment fees are due quarterly. Eurodollar interest payments are due on the last day of the applicable interest period. At March 27, 2020, the term loan and revolving credit facility bore interest at the Eurodollar rate option of 4.44% and 4.19%, respectively.

Term loan principal payments of $2.2 million are due on a quarterly basis. The term loan and revolving credit facility mature on February 15, 2023.