A study released on Sept. 22 by University of Chicago economist Austan Goolsbee found that creating personal investment accounts in Social Security would be "the largest windfall gain in American financial history" for financial services firms.

The study concluded that financial firms would receive $940 billion in management fees from such accounts, costs that would reduce the value of such accounts by 20 percent.

The calculations, who served as an adviser to the presidential campaign of Democrat John Kerry - an opponent of personal accounts - were based on a Social Security reform model devised by the 2001 President's Commission to Strengthen Social Security that would allow workers to divert 4 percentage points of the 12.4 percent Social Security tax to personal accounts.

The full study is available on John Kerry's Web site.