The co-founder of Microsoft, Paul Allen, and its current President, Steve Ballmer, are also high on the list.

World's richest people

Bill Gates: $60bn Larry Ellison: $47bn King Fahd of Saudi Arabia: $30bn Warren Buffett: $28bn Paul Allen: $28bn S. Robson Walton: $20bn Prince Alwaleed Bin Talal Alsaud: $20bn Theo and Karl Albrecht: $20bn Masayoshi Son: $19.4bn Michael Dell: $17.8bn Kenneth Thomson: $16.1bn Steve Ballmer: $15.5bn

Forbes says there are now 482 billionaires in the world, with the richest 200 people now worth $1.1 trillion.

The list is dominated by North Americans, with the Wal-Mart family, Dell Computer founder Michael Dell and Canadian media magnate Kenneth Thomson also among the top ten.

Nearly 60% of all billionaires (308) are from the United States.

But some high-tech magnates have seen their fortunes crash as the boom in high-tech shares cooled since April.

Mr Son, founder of Japanese internet investment firm Softbank, saw his wealth tumble from $68bn in February. But it has still increased three times compared to his position last year.

Japanese mobile phone mogul Yasumitsu Shigeta saw his net worth fall from $39bn to $1.7bn in the same period.

Long-term investor Warren Buffett also saw his wealth decline by $8bn.

The youngest billionaires are Jerry Yang, 31, founder of Yahoo, who is worth $5.9bn, Michael Dell, 36, and Jeff Bezos of internet bookseller Amazon, 36, worth $6.1bn.

Only 12 of the billionaires were women, led by America's Abbey Johnson of mutual fund Fidelity, who is worth $7.4bn.

The only European in the top ten is the secretive Albrecht family, owner of the Aldi chain of discount supermarkets in Germany.

Britain's share

There are fourteen billionaires in Britain, according to the survey.

They include three new magnates: John Hargreaves, founder of discount clothing chain Matalan; Duty Free Shopping's Robert Miller, and Welsh high-tech venture capitalist Terence Matthews.

UK Dollar Billionaires

Duke of Westminster: $5.5bn (�3.7bn) David Sainsbury: $4.1bn (�2.7bn) Sir Richard Branson: $3.3bn (�2.2bn) Bruno Schroder: $2.3bn (�1.5bn) Bernard Ecclestone: $2.2bn (�1.4bn) Terence Matthews: $1.9bn (�1.3bn) Anthony Bamford: $1.8bn (�1.2bn) John Hargreaves: $1.8bn (�1.2bn) Moores family: $1.8bn (�1.2bn) Gary Weston: $1.6bn (�1.1bn) Jonathan Harmsworth: $1.5bn (�1.0bn) Sir Adrian Swire: $1.5bn (�1.0bn) Joseph Lewis: $1.0bn (�600m) Robert Miller: $1.0bn (�600m)

Britain now has more billionaires than France (13), but considerably fewer than Germany (39).

But unlike some other countries, the rich in Britain have mainly gained their wealth through retailing or media, not high-tech ventures.

Their wealth comes from supermarkets (David Sainsbury), bread-making (Gary Weston), newspapers (Jonathan Harmsworth), records and aeroplanes (Richard Branson, Adrian Swire), construction equipment (Anthony Bamford), and Littlewoods pools (Moores family).

But the richest man in Britain is still property owner, the Duke of Westminster, who inherited his central London estates.

The Queen is only worth $450m, according to Forbes, if you do not count the possessions she holds in trust for the nation, like the Crown Jewels.

If these were counted, she would be worth $16bn (�11bn), and would be the richest person in Britain.

The Forbes list is based on stock market prices as of 22 May and estimates of the value of privately held companies.