A widely watched measure of future economic activity rose in November as fewer people filed for jobless benefits, suggesting the nation's economy may grow moderately into the spring, a private research group said Thursday.

The Conference Board said its Index of Leading Economic Indicators, which tries to gauge future economic growth, rose 0.5 percent in November.

Much of last month's gains were tied to a drop in applicants seeking unemployment benefits. That number had spiked soon after Hurricane Katrina devastated U.S. Gulf States.

While the outlook signals the economy will grow, the report's authors warned of rising costs tied to higher energy prices.

"High and potentially rising energy prices are one consideration in this outlook," said Ken Goldstein, labor economist at The Conference Board. "Rising costs and questions about whether they will be matched by price hikes are also a factor in how fast the economy grows this spring."

Much of the jump in energy prices has been tied to disruptions from Hurricane Katrina, which roiled the oil and gas industry. The higher prices, felt at first by car owners filling up their gas tanks, are now affecting a wide range of industries which rely on petroleum-based products, like plastics, utilities and transportation.

The Conference Board's measure of current economic activity, the coincident index, rose 0.2 percent in November, following a 0.2 percent increase in October. The research group said that over the last six months, industrial production and employment have been the engines of growth in its coincident index.