The latest list of the world's billionaires, compiled by Forbes magazine, contains 47 more names than last year.
The rest of the world outside the US has 238 entrants worth dollars 514bn. Forty-two are German, 36 Japanese and a surprising 24 come from Mexico. Forbes notes that the booming economies of Latin America are now producing more new billionaires than any other region of the world.
Topping the Forbes list is the family of the late Sam Walton, who made his fortune through his retailing chain. The Waltons are estimated to be worth dollars 23.6bn, more than double the dollars 9.6bn net worth of the second- placed Mars family, of chocolate bar fame.
Bill Gates, founder of Microsoft, is the richest US individual on the list, having edged ahead of the stock market investor Warren Buffet since last year. Mr Gates' net worth is listed as dollars 8.2bn, just behind the Japanese property and railways magnate Yoshiaki Tsutsumi's dollars 8.5bn.
Britain makes a modest contribution with five entries. David Sainsbury and his supermarket owning family come out on top at dollars 4.4bn, followed at dollars 2.2bn by Garry Weston and family, controlling shareholders of Associated British Foods.
The family of the late John Moores, the football pools tycoon who died last year aged 97, is listed as worth dollars 1.8bn, while the entrepreneur Richard Branson weighs in at dollars 1.1bn. Completing the UK entrants is the Schroder family, which founded the investment bank 176 years ago.