As Trucking Goes, So Goes The Economy

But there is no sign of that yet in the current recession. The ATA said shipments fell 4.5 percent in March, erasing gains that made the industry cautiously optimistic in the two previous months.

Shipment volume has already fallen more in this downturn than it did in the recession of 2001, Headley said.

Headley said a number of factors may influence how much time will pass between sustained shipping improvement and a stronger economy. For one thing, how fast retailers go through existing inventories will affect how quickly new orders begin.

Lower fuel prices are not necessarily helping the trucking industry either. Less costly fuel has made it easier for struggling companies to stay afloat — good for them, but bad for the industry overall because competition remains fierce. So truckers must cut their prices to hold on to business.

Diesel prices are less than half what they were in July, when they shot up to around $5 a gallon. The national average for on-highway diesel is now about $2.19 a gallon, according to the Energy Information Administration.

"It doesn't matter what fuel costs are if you're not moving your truck to fill it with something," said Chuck Clowdis, an analyst with private forecasting firm IHS Global Insight.