The Milken Institute, an economics research group in Santa Monica, Calif., that studied 315 cities, said the losses would spread across industries including restaurants, financial services and aerospace.

"The consequences of Sept. 11 for individuals and unique localities have been profound," the report said.

The report said that 248,000 jobs had already been lost because of the attacks and that an additional 1.6 million jobs were expected to be lost this year.

New York City should lose nearly 150,000 more jobs; followed by Los Angeles, with 69,000 jobs; and Chicago with at least 68,000, the report said. Las Vegas should prove the most vulnerable metropolitan region in percentage terms. The report said it was most likely to see nearly 5 percent fewer jobs this year.

"The good news is that many of those jobs should come back," said Ross DeVol, director of regional studies at the institute.

The researchers expect most cities to begin to recover next year, with the exception of New York, which should start its rebound in 2004. New York lost billions of dollars worth of assets and thousands of jobs directly related to the shutdown of its financial district in the week after the attacks.

The Labor Department, which compiles job losses, found a total of 1.1 million jobs were lost from September through December. Those four months account for all but 300,000 of the jobs lost since the economic recession began in March, the department's statistics show.

The Milken report used economic models to extrapolate employment losses based on each metropolitan region's trends before Sept. 11.

Of the estimated 1.6 million losses this year that the study ties to Sept. 11, 760,000 will be directly related to the attacks, with two-thirds of those in travel and tourism.

The largest decline will be in aviation, accounting for 20 percent of the lost jobs, the report said. Spending on airline travel dropped 38 percent in September, a decline of $12.5 billion, and improved modestly in October.

"We do feel the impact, and it hurts," said Erika Brandvik, a spokeswoman for the Las Vegas Convention and Visitors Authority. "But nobody ever gets a long-term feeling of doom and gloom about the Las Vegas economy. We have a record of recovery."