[Background Knowledge]A look at some key industries in the United States shows that the economic recovery is a bit erratic and growth seems to be slowing down.
Economists say trucks haul nearly 70 percent of the freight used in the United States.
The American Trucking Association says freight is a measure of the economy, because manufacturers have to move raw materials, carry parts to factories, haul imports and exports and deliver goods to store shelves.
“We are actually a very good indicator, a leading economic indicator ((a way of looking at the economic future)) in fact. And so if tonnage starts to fall, we get nervous. If it’s going up, we are pretty happy,“ said Bob Costello, the group's chief economist.
Freight tonnage is going up at the moment, but the rate of growth is slowing down.
"It is telling me that the economy is not falling into another recession. It will continue as a sort of a slow growth recovery," Costello said.
Other clues about economic growth come from the volume of air freight. The most recent data show demand for air freight fell more than three percent globally during July.
"It can also, as you start to see air cargo dropping off and you are seeing other signs -- it can also be a leading indicator of a downturn,” said Perry Flint, of the International Air Transport Association.
However, the same report shows that passenger traffic made gains during the same period.
That may be why a top official of Cambria Suites Hotels, Michael Murphy, says business is strong.
“We are seeing the highest demand in the history of the hotel industry right now. More people are traveling now than ever before, and that's in all segments of travel,” Murphy said.
The contradictory indicators are one reason that predicting the economic future is a complex and difficult task.
For example, government experts first said the U.S. economy expanded at a 1.5 percent annual rate during April, May, and June. Then they made a revision -- as new information became available and showed growth was more likely at a 1.7 percent rate.
Trying to figure out what to do about the sluggish economic recovery is even more complicated.