Freight spending rose by double digits in Q3, buoyed by tight trucking market.

Freight spending increased by double digits in the third quarter compared to the same period in 2017 despite lower freight shipment volumes, reflecting rising average freight transaction prices, according to the latest quarterly index of U.S. freight activity from financial services giant U.S. Bank.

However, that bill could have been even higher, since freight spending slowed slightly in the third quarter compared to the second quarter of 2018, under the weight of a moderating U.S. economy, storm damage from Hurricane Florence, and early impacts of rising tariffs in a growing trade war, the bank said.

The Minneapolis-based bank produces its U.S. Bank Freight Payment Index based on information submitted by companies that use the bank to process and audit their freight payments. The report tracks a comparative measure of spending, not absolute dollar values.

By those numbers, the amount spent on U.S. freight costs in the third quarter decreased 1.2 percent from the second quarter, but is up 13.5 percent from the same period last year. At the same time, U.S. freight shipment volume in the third quarter decreased 5.2 percent from the second quarter and is down 1.1 percent from the same period last year.

Spend remained high despite the drop in volume because of constrained trucking capacity due to an ongoing commercial driver shortage, according to Bob Costello, a freight industry analyst and chief economist for American Trucking Associations who provides commentary on each report.

"Linked quarter declines in both freight shipment volume and spend are in line with the deceleration many expected in third quarter gross domestic product growth," Costello said in a statement. "As trucking often leads the broader economy, the decreases seen in the U.S. Bank Freight Payment Index suggest economic growth may have peaked and may decelerate in the fourth quarter and beyond. Despite the sequential decreases in freight shipments and spending last quarter, the national truck market remains solid and capacity tight."

U.S. Bank's warning of a looming slump in U.S. economic growth is in line with recent forecasts from other economists, who have noted that the country is on track for a moderate recession in 2020. Factors contributing to the trend include rising interest rates and the impact of trading tariffs levied by the Trump Administration, economists and retail trade groups say.