ARLINGTON, Va. — American Trucking Associations‘ advance seasonally adjusted For-Hire Truck Tonnage Index increased 1.7 percent in September after falling 2.8 percent in August.

The non-adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, equaled 112.4 in September, down 0.9 percent from the previous month.

Compared with September 2009, tonnage climbed 5.1 percent, which was well above August’s 2.9 percent year-over-year gain. Year-to-date, tonnage is up 6.1 percent compared with the same period in 2009.

"While I am glad to report that tonnage grew in September, the fact remains that truck freight volumes leveled off over the summer and early autumn," said ATA’s chief economist, Bob Costello. "This is a reflection of an economy that is barely growing."

Costello noted again this month that the trucking industry is significantly smaller than it was prior to the recession, but as a result, is better equipped to deal with slower than normal tonnage growth.

Trucking serves as a barometer of the U.S. economy, representing 68 percent of tonnage carried by all modes of domestic freight transportation, including manufactured and retail goods.