Truck tonnage saw another monthly decline in June, according to data issued today by the American Trucking Associations (ATA). ATA reported that its June Seasonally Adjusted (SA) For-Hire Truck Tonnage Index reading, at 113.1 (2015=100), saw a 0.7% annual decrease (downwardly revised from an originally-reported 0.6% annual decrease), following a 2.5% annual increase in April. The ATA’s not seasonally adjusted (SA) For-Hire Truck Tonnage Index, which represents the change in tonnage actually hauled by fleets before any seasonal adjustment and the metric ATA says fleets should benchmark their levels with, came in at 116.5, topping May’s 113.4 reading by 2.7%. ATA said that these indices “are dominated by contract freight, as opposed to traditional spot market freight.” “After five straight year-over-year gains, tonnage has now contracted from year-earlier levels for the last two months.