American Trucking Associations’ advanced seasonally adjusted for-hire truck tonnage index fell 6.2% in December, following a revised 8.4% jump during November.

In December, the index equaled 133.8 (2000=100), down from 142.7 in November. The all-time high was 144 in February 2016.

Compared with December 2015, the index decreased 0.7%. In November, the index increased 5.9% on a year-over-year basis. For all of 2016, tonnage was up 2.5%.

The not seasonally adjusted index, which represents the change in tonnage actually hauled by the fleets before any seasonal adjustment, equaled 133.9 in December, which was 1.6% below the previous month (136.1).

“The ups and downs that plagued most of 2016 continued in December,” said Bob Costello, ATA’s chief economist. “I don’t recall a year in recent memory with so many large swings on a month-to-month basis. Looking ahead, there are some positive signs for truck tonnage. This includes the continued spending by consumers, larger wage gains and solid home construction. Factory output will continue to be soft, but it should be better this year than last year. And most importantly, the supply chain continues to make progress reducing bloated inventories, which will help truck volumes going forward.”