Despite third-quarter earnings that were up 8 percent over the same period in 2006 and beat analysts' expectations, the Fort Worth, Texas-based company said it was concerned about the short-term prospect of a slowing economy, weak housing markets, sluggish consumer spending and high fuel prices.

Chairman and Chief Executive Matthew K. Rose said the company was not buying out employees to remove them from the payroll, but was seeing attrition of about 2 percent per year and wouldn't increase the work force until shipping volumes resume.

Burlington Northern said freight volumes fell by 4.7 percent due to weakness in the housing market, which dinged shipments of furniture, and in consumer goods.

But agricultural shipments rose 10 percent, to $682 million, behind strong demand for wheat and for corn used to produce ethanol. And revenue from coal shipments jumped 14 percent, or $101 million, to $849 million, even though volumes were virtually flat due to mine production problems, the railroad said.

For the fourth quarter, Burlington expects freight revenue to grow by a mid-single-digits percentage, with pricing remaining strong and volumes turning down slightly.

Over the next couple months, shipments of holiday goods could be hit by the trend of shoppers buying gift cards, which often aren't redeemed right away, delaying the need for retailers to ship goods by rail to stores before December, executives said.

"Although we have concerns near-term about the economy, housing markets, high fuel prices and general consumer softness, we continue to be optimistic about the long-term future of BNSF," Rose said.

Rose did not say when he expected shipping volumes to resume to a level considered acceptable.

BNSF spokesman Steve Forsberg downplayed Rose's comments, which came during a conference call Tuesday.

He said the size of the company's workforce has always varied with the volume of traffic, although BNSF has been on somewhat of a growth spurt recently, growing from 36,500 employees in 2003 to about 40,000 currently.

At last count, BNSF had about 1,800 employees in Lincoln, according to Forsberg, up about 400 people from 2002, but down from more than 2,000 in the mid-1990s

Despite the dreary short-term outlook BNSF delivered Tuesday, investors saw much to like in the company's earnings report, as shares were up more than 4 percent in afternoon trading on the New York Stock Exchange.

The company said it earned $530 million, or $1.48 per share, in the quarter ended Sept. 30, compared with $489 million, or $1.33 per share, a year earlier.