American Trucking Associations' advance seasonally adjusted (SA) For-Hire Truck Tonnage Index increased 1.7 percent in September after falling a revised 2.8 percent in August.
The latest gain put the SA index at 108.7 (2000=100) in September from 106.9 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, SA 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.

ATA's chief economist, Bob Costello, said that truck tonnage over the last few months fits with an economy that is growing very slowly.

"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. 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.
Trucks hauled 8.8 billion tons of freight in 2009. Motor carriers collected $544.4 billion, or
81.9 percent of total revenue earned by all transport modes.

ATA calculates the tonnage index based on surveys from its membership and has been doing so since the 1970s. This is a preliminary figure and subject to change in the final report issued around the 10th day of the month. The report includes month-to-month and year-over-year results, relevant economic comparisons, and key financial indicators.