The number of Russian billionaires fell from 87 to 32, with 27 in Moscow.
It means that New York, with 55 people on the list, has regained the title of billionaire capital of the world from Moscow. London was second with 28.
Russia's richest man, aluminium magnate Oleg Deripaska, saw his fortune plummet from $28bn (£20.3bn) to $3.5bn.
With fortunes falling in Russia and Asia, the US dominated the list of the super-rich.
Microsoft founder Bill Gates regained top spot and Americans made up half of the top 20, compared with only four last year.
