The total wealth of Russia's 100 richest people was put at $142 billion by the magazine, compared to $552 billion at this time last year. The total number of Russian billionaires also fell dramatically, from 110 to 32.
Forbes said the largest tumble in wealth was experienced by Oleg Deripaska, the head of holding company Basic Element, who topped the list with $28.6 billion in 2008, and dropped to number 10 with a net wealth of $3.5 billion this year.
The new Forbes list is topped by Oneksim Group owner, Mikhail Prokhorov, with $9.5 billion, followed by the Millhouse Company and Chelsea FC owner Roman Abramovich ($8.5 bln), and the president of LUKoil, Vagit Alekperov ($7.8 bln).
Forbes also noted that no one in the top 100 had increased their wealth, just that some had lost more than others.
Yelena Baturina, the wife of Moscow mayor Yury Luzhkov, was the only woman in the top 100 for the second year in a row, in 32nd place. Baturina, the president of the construction conglomerate Iteka, has lost some $4.2 billion, leaving her with a total wealth of $900 million, Forbes said.
The average age of the Forbes' list is 47 years and six months.