The flooding has displaced about 1 million workers in the Gulf Coast region, many of whom will not be able to resume their jobs anytime soon. While some employees of large companies are still receiving paychecks, Wal-Mart stopped paying workers in the area four days after shutting its stores, and McDonald's and UPS have not paid regular wages to employees since the storm hit.

The hurricane has also bottled up grain shipments on the Mississippi River, hurting farmers and grain exporters, and has saddled households with even higher energy costs.

The effect of the damage to oil rigs and refineries in the Gulf of Mexico is the greatest uncertainty. But contrary to early fears, the nation's transportation network has not become overwhelmed so far, and despite spot shortages drivers have generally been able to buy gasoline. The price of crude oil fell 2 percent Friday - to $67.57, up only $1 from a week ago - as a large importing terminal off the coast of Louisiana reopened and the International Energy Agency announced that it would release emergency oil supplies.

As corporate executives scrambled to contact employees who lived in Katrina's path, most said they had seen little overall effect on their business.

''It's a little too early to tell,'' said Fred Beljaars, the executive vice president of DHL, the shipping company. ''But the first indications are that there is no real impact on trade.''

Economists said that the storm and its aftermath had raised the risks of a downturn. One major question is whether the damage to oil refineries aggravates what had already been a growing burden caused by soaring energy prices.

''The difference with this disaster is that we have an energy shock,'' said Laurence Meyer, an economist at Macroeconomic Advisers, a forecasting firm.

But the most likely outcome, according to forecasts that Wall Street firms revised after the storm, is a slowdown in growth during the rest of this year and a pickup next year, as New Orleans and southern Mississippi are rebuilt.

Outside the immediate area, the biggest economic problems have come along the Mississippi River corridor. The Port of New Orleans is the nation's fifth busiest, and its closure has stranded barges in the Midwest.