ARLINGTON, Va. — The American Trucking Associations‘ advance seasonally adjusted For-Hire Truck Tonnage Index increased 2.8 percent in June after slipping 2 percent the previous month.

The latest gain put the SA index at 115.8 (2000=100) in June, up from the May level of 112.6 and the highest since January 2011.

The index, which represents the change in tonnage actually hauled by the fleets, equaled 122.3 in June, which was 5.3 percent above the previous month.

Compared with June 2010, SA tonnage jumped 6.8 percent — the largest year-over-year gain since January 2011.

"Motor carriers told us that freight was strong in June and that played out in the data as well," ATA Chief Economist Bob Costello said. Tonnage recovered all of the losses in April and May, he added.

"After growing 5.5 percent in the first half of the year from the same period last year, the strength of truck tonnage in the second half will depend greatly on what manufacturing output does," Costello noted. "If manufacturing continues to grow stronger than GDP, I fully expect truck freight to do the same."