Truck tonnage ended the year strong in 2012, according to the American Trucking Associations’ for-hire truck tonnage index. Following a 3.9-percent rise in November, the ATA measured a 2.8-percent increase in its index for December. These month-over-month increases were the biggest gains of the year, but December’s year-over-year growth tells a different story. Compared to December 2011, last month’s total showed a decline of 2.3 percent, the lowest year-over-year gro...