ARLINGTON, VA — For-hire truck tonnage moved in the U.S. recovered somewhat in May while the decline the month before was cut by just over half.

According to the American Trucking Associations’ seasonally adjusted For-Hire Truck Tonnage Index, activity increased 1.1 percent last month following a revised decline of 1.4 percent in April, first reported as a 3% drop.

This pushed the index to a reading of 132.1 compared to the all-time high of 135.8 hit in January 2015.

Compared with May 2014, the seasonally adjusted index increased just 1.8 percent, which was well below the 2.7 percent gain in April and the smallest year-over-year gain since February 2013.

Year-to-date through May, compared with the same period last year, tonnage is up 3.7 percent.

The not seasonally adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, equaled 133.1 in May which was 0.3 percent above the previous month at 132.7.

“The good news is that truck tonnage increased in May,” said ATA Chief Economist Bob Costello. “But tonnage is certainly not strong at the moment as factory output is soft and there is an inventory reduction occurring throughout the supply chain.”

Costello noted that truck tonnage is off 2.7 percent from the high in January.

“I believe the inventory correction should end this summer and truck freight, helped by better personal consumption, will accelerate,” he said, “which is good because I think it is unlikely factory output will boost truck tonnage much until later this year or next year.”

Trucking serves as a barometer of the U.S. economy, representing 68.8 percent of tonnage carried by all modes of domestic freight transportation, including manufactured and retail goods, according to ATA.