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The world's billionaires have been hit hard by the global downturn, but two software entrepreneurs still feature in the top five.
The co-founder of Microsoft was third last year with a massive £41bn, according to the rich list produced by business magazine Forbes.
This year, Oracle chief Larry Ellison is the forth richest person with £16.2bn, compared to £18bn a year ago.
Warren Buffet, who heads investment conglomerate Berkshire Hathaway, has been demoted to second with £26.7bn compared to £44bn the previous year.
Among those experiencing significant falls in their net worth was Facebook founder Mark Zuckerberg, who lost his billionaire status.