LONG-TERM DEBT

Long-term debt consisted of the following (in thousands):



	March 31, 2019		December 31, 2018
Revolving credit agreement	$	92,450	$	85,300

On January 31, 2019, USA Truck, Inc., a Delaware corporation (the "Company"), entered into a five years, $225.0 million senior secured revolving credit facility (the "New Credit Facility") with a group of lenders and the Agent pursuant to the terms of an Amended and Restated Loan and Security Agreement that amends and restates the terms of the Company's previous five years, $170.0 million senior secured revolving credit facility dated February 15, 2015.

The Credit Facility is structured as a $225.0 million revolving credit facility, with an accordion feature that, so long as no event of default exists, allows the Company to request an increase in the revolving credit facility of up to $75.0 million, exercisable in increments of $20.0 million. The Credit Facility is a five year facility scheduled to terminate on January 31, 2024. Borrowings under the Credit Facility are classified as either “base rate loans” or “LIBOR loans”. Base rate loans accrue interest at a base rate equal to the Agent’s prime rate plus an applicable margin set at 0.25% through June 30, 2019, and adjusted quarterly thereafter between 0.25% and 0.75% based on the Company’s consolidated fixed charge coverage ratio. LIBOR loans accrue interest at the London Interbank Offered Rate (“LIBOR”) plus an applicable margin set at 1.25% through June 30, 2019, and adjusted quarterly thereafter between 1.25% and 1.75% based on the Company’s consolidated fixed charge coverage ratio. The Credit Facility includes, within its $225.0 million revolving credit facility, a letter of credit sub-facility in an aggregate amount of $15.0 million and a swingline sub-facility (the “Swingline”) in an aggregate amount of $25.0 million. An unused line fee of 0.25% is applied to the average daily amount by which the lenders’ aggregate revolving commitments exceed the outstanding principal amount of revolver loans and the aggregate undrawn amount of all outstanding letters of credit issued under the Credit Facility. The Credit Facility is secured by a pledge of substantially all of the Company’s assets, except for any real estate or revenue equipment financed outside the Credit Facility.

Borrowings under the Credit Facility are subject to a borrowing base limited to the lesser of (A) $225.0 million; or (B) the sum of (i) 90% of eligible investment grade accounts receivable (reduced to 85% in certain situations), plus (ii) 85% of eligible non-investment grade accounts receivable, plus (iii) the lesser of (a) 85% of eligible unbilled accounts receivable and (b) $10.0 million, plus (iv) the product of 85% multiplied by the net orderly liquidation value percentage applied to the net book value of eligible revenue equipment, plus (v) 85% multiplied by the net book value of otherwise eligible newly acquired revenue equipment that has not yet been subject to an appraisal. The borrowing base is reduced by an availability reserve, including reserves based on dilution and certain other customary reserves.

The Credit Facility contains a single financial covenant, which requires a consolidated fixed charge coverage ratio of at least 1.0 to 1.0 that is triggered in the event excess availability under the Credit Facility falls below 10% of the lenders’ total commitments. Also, certain restrictions regarding the Company’s ability to pay dividends, make certain investments, prepay certain indebtedness, execute share repurchase programs and enter into certain acquisitions and hedging arrangements are triggered in the event excess availability under the Credit Facility falls below 10% of the lenders’ total commitments.

The Company had no borrowings under the Swingline as of March 31, 2019. The average interest rate including all borrowings made under the Credit Facility as of March 31, 2019 was 3.88%. As debt is repriced on a monthly basis, the borrowings under the Credit Facility approximate fair value. As of March 31, 2019, the Company had outstanding $5.4 million in letters of credit and had approximately $50.0 million available to borrow under the Credit Facility.