While the rest of New York City's economy has begun to recover, there is no upturn in sight for lower Manhattan.

Downtown has lost 62,683 jobs since Sept. 11, or about 16% of the total 400,000 jobs below Canal Street as of Sept. 10, according to brokerage TenantWise.com Inc.

Only about 53% of the 137,919 jobs displaced by the terrorist attack have returned or are returning to the neighborhood. The rest have left for midtown, other parts of New York City, or the suburbs.

TenantWise says the 337,317 remaining jobs are at risk as leases expire over the next five to 10 years. Many firms will leave because of safety, environmental and transportation concerns. In addition, says TenantWise Chief Executive Myers Mermel, "A lot of firms have decided they don't want to be in a construction zone."