American Trucking Associations’ advanced seasonally adjusted For-Hire Truck Tonnage Index increased 6.6% in all of 2018 – the largest annual gain since 1998 and significantly better than the 3.8% increase in 2017.

This is despite a 4.3% decrease in December which brought the index down to 111.9 from a high of 116.9 in November. Compared to December 2017, the index was 1.4% higher, the smallest monthly year-over-year increase in 2018. For comparison, in November, the index was 5.8% above the same month in 2017.

The not seasonally adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, equaled 107.8 in December, which below the previous month’s reading of 117. In calculating the index, 100 represents 2015.

“The good news is that 2018 was a banner year for truck tonnage, witnessing the largest annual increase we’ve seen in two decades,” said Bob Costello, ATA chief economist. “With that said, there is evidence that the industry and economy is moderating as tonnage fell a combined total of 5.6% in October and November after hitting an all-time high in October.”