American Trucking Associations’ advanced seasonally adjusted (SA) For-Hire Truck Tonnage Index slipped 0.9% in September, following a 4.7% gain during August. In September, the index equaled 144.4 (2000=100), down from 145.7 in August.

Compared with September 2016, the SA index surged 7.4%. In August, the index increased 5.8% on a year-over-year basis. Year-to-date, compared with the same nine months in 2016, the index was up 2.4%.

As part of this report, ATA also revised its August increase in the index down to a 4.7% gain from the previously reported 7.1% increase.

The not seasonally adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, equaled 145.3 in September, which was 5% below the previous month (152.9).

“Tonnage gave back some of the solid gain in August, but remains at very high levels despite the weather-related issues during the month,” said Bob Costello, ATA chief economist. “Going forward, rebuilding from those hurricanes and other natural disasters like the wildfires in California will add to freight demand.

“September’s small setback doesn’t worry me. Freight has been improving and I would have thought tonnage last month would have been softer than it was,” he said.