ARLINGTON, VA – The amount of truck tonnage moved in the U.S. fell in August but it remains not far from its recent record high, according to a new report.

The American Trucking Associations’ advanced seasonally adjusted For-Hire Truck Tonnage Index declined 0.9 percent, following a revised increase of 3.1 percent during July.

In August, the index equaled 134.2, down from 135.3 in July, but close to the all-time high of 135.8 reached in January.

Compared with August 2014, the index increased 2.1 percent, which was below the 4 percent gain in July. Year-to-date through August, compared with the same period last year, tonnage is up 3.3 percent.

The not seasonally adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, equaled 137.0 in August, only 0.5 percent below the previous month’s reading of 137.6.

“After such a robust July, it is not too surprising that tonnage took a breather in August,” said ATA Chief Economist Bob Costello. “The dip after a strong gain goes with the up and down pattern we’ve seen this year.”

Costello said a few factors hurt August’s reading, including soft housing starts and falling factory output.

“As I said last month, I remain concerned about the high level of inventories throughout the supply chain. This could have a negative impact on truck freight volumes over the next few months,” he said.

According to ATA, trucking serves as a barometer of the U.S. economy, representing 68.8 percent of tonnage carried by all modes of domestic freight transportation. It calculates the tonnage index based on surveys from its members.