On a seasonally adjusted basis, the tonnage index increased to 110.9 (2000 = 100) in July, which was the highest reading since April. Despite July's sequential gain, tonnage was down 3.7 percent from a year earlier. Year-to-date the tonnage index was 2.6 percent lower than the same period in 2006.
ATA Chief Economist Bob Costello said July's tonnage reading points to continued softness in the trucking industry, specifically as it relates to the weight of goods shipped. Costello noted, however, that other measures of trucking volumes are not as lackluster. The number of for-hire loads, for example, which ATA publishes in a separate report, increased 0.4 percent during the first half of 2007 on a year-over-year basis.
"The weakness in the residential construction market continues to have a disproportionately larger impact on truck tonnage than the number of loads transported," Costello said. "Construction freight on average weighs more than general freight. As a result, the weakness in the construction market is having a bigger impact on truck tonnage."
Several trends indicate a modest 2007 fall freight season. Shippers increasingly spread the peak season over more months, the housing market is expected to remain down and economists predict only moderate economic growth in the near term, Costello said.
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, 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 10th day of the month. The report includes month-to-month and year-over-year results, relevant economic comparisons, and key financial indicators.