The American Trucking Associations' advance seasonally adjusted For-Hire Truck Tonnage Index was up 2.1 percent in August, a repeat of July's booost.
The index lands at 104.1 in August, making it the best reading since February. (The year 2000 is the base year at 100).

Tonnage fell 7.5 percent in August from the same month last year, the best year-to-year showing since November 2008, ATA said.

The not-seasonally adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, was down 0.5 percent from July, to 105.8.

Bob Costello, ATA chief economist, said that the latest increase was another positive sign for the industry. "The gains in tonnage during July and August reflect a growing economy and less of an overhang in inventories," he said.

While he is hopeful that tonnage will trend upwards in the months ahead, he believes the pace of increase will likely be moderate from the cumulative 4.3 percent gain over the last two months. "While I am optimistic that the worst is behind us, most economic indicators, including industrial output and household spending, suggest freight tonnage will exhibit moderate, and probably inconsistent, growth in the months ahead," Costello said.