The American Trucking Associations’ advanced seasonally adjusted for-hire Truck Tonnage Index decreased 2.1 percent in August. The setback was preceded by a 0.7 percent gain in July.

On a seasonally adjusted basis, the tonnage index fell to 110.9 (2000=100) from 113.3 in July. August’s index level is the lowest reading since tonnage stood at 110.4 in March of this year and is now 2.9 percent lower than a year earlier.
Year-to-date, the truck tonnage index is down 2 percent, compared with the same period in 2005. The not-seasonally adjusted index jumped 6.8 percent from July to 116.5.
“Freight volumes typically increase between July and August, but the gain this year wasn’t strong enough to push the seasonally adjusted reading into positive territory,” said ATA Chief Economist Bob Costello. “The dramatic fall in the housing sector in recent months impacted August truck tonnage, specifically flatbed freight. Although there is not as much flatbed tonnage as dry van tonnage, a slowdown in flatbed freight weighed down the overall figure.”
Costello said general freight truckload gains were in line with anecdotal reports that suggest the fall freight season started with a whimper rather than a roar, much like last year.
Trucking serves as a barometer of the U.S. economy because it represents nearly 70 percent of tonnage carried by all modes of domestic freight transportation, including manufactured and retail goods.
Trucks hauled 10.7 billion tons of freight in 2005. Motor carriers collected $623 billion dollars, or 84.3 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 tenth day of the month. The report includes month-to-month and year-over-year results, relevant economic comparisons, and key financial indicators.