The American Trucking Associations' advance seasonally adjusted (SA) For-Hire Truck Tonnage Index increased 1.5 percent in July, although June's reduction was revised from 1.4 percent to 1.6 percent. 'The latest improvement raised the SA index from 108.3 (2000=100) in June to 110 in July.

The not seasonally adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, equaled 109.9 in July, down 5 percent from the previous month.'

Compared with July 2009, SA tonnage climbed 7.4 percent, which matched June's increase and was the eighth consecutive year-over-year gain. Year-to-date, tonnage is up 6.7 percent compared with the same period in 2009.'

ATA Chief Economist Bob Costello said that July's data didn't change his outlook for subdued tonnage growth in the months ahead, stating, 'The economy is slowing and truck freight tonnage has essentially gone sideways since April 2010.'' Nevertheless, Costello believes that tonnage will post moderate gains, on average, for the second half of the year.' 'After accounting for the reduction in supply over the last few years, even small gains in tonnage will have a larger impact on the industry than in past.'

Note on the impact of trucking company failures on the index: Each month, ATA asks its membership the amount of tonnage each carrier hauled, including all types of freight.' The indexes are calculated based on those responses.' The sample includes an array of trucking companies, ranging from small fleets to multi-billion dollar carriers. When a company in the sample fails, we include its final month of operation and zero it out for the following month, with the assumption that the remaining carriers pick up that freight.' As a result, it is close to a net wash and does not end up in a false increase.' Nevertheless, some carriers are picking up freight from failures, and it may have boosted the index. Due to our correction mentioned above, however, it should be limited.

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.