The American Trucking Associations’ advanced seasonally adjusted (SA) For-Hire Truck Tonnage Index increased 1.2% in June after falling 1.0% in May. (May’s loss was larger than the 0.7% drop ATA reported on June 19.)

June’s increase was the largest month-to-month gain in 2012. However, the index contracted a total of 2.1% in April and May. The latest gain increased the SA index to 119.0 (2000=100), up from May’s level of 117.5. Compared with June 2011, the SA index was 3.2% higher, the smallest year-over-year increase since March 2012. Year-to-date, compared with the same period last year, tonnage was up 3.7%.

“June’s increase was a pleasant surprise, but the lower year-over-year gain fits with an economy that has slowed,” ATA Chief Economist Bob Costello says. “Manufacturing output was strong in June, which helped tonnage levels.”

The not-seasonally-adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, equaled 123.0 in June, which was 0.9% below the previous month. For the second quarter, the SA index was off 0.8% from the previous quarter, which was the first decrease in a year. Compared with the second quarter in 2011, the index was up 3.5%.

Costello says he’s still concerned about businesses sitting on cash instead of hiring more workers or spending it on capital investments, both of which would give the economy and tonnage a shot in the arm, as they are worried about Europe and the US fiscal cliff at the end of the year. Costello lowered his tonnage outlook for 2012 to the 3% to 3.5% range due to recent economic weakness.