The American Trucking Associations’ advanced seasonally adjusted For-Hire Truck Tonnage Index increased 2.8% in February, after plunging 4.5% the previous month. January’s drop was slightly more than the 4.3% reported on February 19, 2014. In February, the index equaled 127.6 (2000=100) versus 124.1 in January. The all-time high was in November 2013 (131.0).

Compared with February 2013, the SA index increased 3.6%. Year-to-date, compared with the same period last year, tonnage is up 2.3%.

The not seasonally adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, equaled 116.5 in February, which was 4.5% below the previous month (122).

“It is pretty clear that winter weather had a negative impact on truck tonnage during February,” said ATA Chief Economist Bob Costello. “However, the impact wasn’t as bad as in January because of the backlog in freight due to the number of storms that hit over the January and February period.”

“The fundamentals for truck freight continue to look good,” he said. “Several other economic indicators also snapped back in February. We have a hole to dig out of from such a bad January, but I feel like we are moving in the right direction again. I remain optimistic for 2014.”

Trucking serves as a barometer of the U.S. economy, representing 68.5% of tonnage carried by all modes of domestic freight transportation, including manufactured and retail goods. Trucks hauled 9.4 billion tons of freight in 2012. Motor carriers collected $642.1 billion, or 80.7% 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.