The national average retail price of diesel fuel fell below $2 a gallon, passing yet another long-standing threshold after setting an 11-year low the previous week, the Department of Energy reported.

Daimler Trucks North America announced another round of layoffs that includes about 700 workers from its medium-duty plant in Mount Holly, North Carolina, and an additional 500 at its Class 8 plant in Cleveland, North Carolina.

Industry suppliers Rush Enterprises Inc. and Allison Transmission Holdings Inc. said net income and revenue dropped in the fourth quarter and that they were taking a guarded approach to 2016.

While politicians, Hill aides and lobbyists worked on or against legislation that would have allowed twin 33-foot trailers on the national highway system, manufacturers and their fleet customers took note, and the trailer makers busied themselves with improving techniques for stretching 28-foot pup trailers into 33-footers.

Instead of waiting for diesel prices to rise, truck makers and their suppliers should try to cash in on the environmental benefits of natural gas, experts said.

The U.S. retail diesel average price fell for the 13th consecutive week, dropping 2.3 cents a gallon to $2.008 and setting a record low in the era of ultra-low-sulfur fuel, the Department of Energy reported.

January’s Class 8 North American orders just cleared 18,000, down 48% year-over-year but within expectations as fleets’ ordering patterns shifted into a more typical range, analysts said.