The American Trucking Associations’ advanced seasonally adjusted For-Hire Truck Tonnage Index increased 2.9 percent in January after jumping 2.4 percent in December. Tonnage has surged at least 2.4 percent every month since November, gaining a total of 9.1 percent over that period. Seasonally adjusted data takes into account items such as weather, increased factory production for certain times of the year, harvests and back-to-school sales. More