The average billionaire has four homes worth nearly US$20 million each, an art collection worth US$14 million and is most likely to live in Europe, the inaugural Wealth-X and UBS Billionaire Census shows. But New York topped the list as the city with the most billionaires - 96. Hong Kong came in second, with 75 billionaires living and primarily conducting their business it the city, closely followed by Moscow with 74. Beijing, in seventh place, was the top mainland city with 26 billionaires. It was followed by Shanghai, which ranked 16th with 19 billionaires, and Shenzhen in 19th spot with 16. "There's really no such thing as an 'average' billionaire, but as we look at numbers, the average billionaire has a net worth of US$3 billion, cash equivalents of US$545 million, an average of 2.1 children, is 63 years of age and possesses luxury assets and personal holdings of US$136 million," Mykolas Rambus, the chief executive of Wealth-X, said yesterday. "It's also worth noting that 15 per cent of billionaires have four children or more." The census was the first comprehensive worldwide study of billionaires. The global billionaire population reached a record 2,170 this year - "far more ever than identified or understood", Rambus said. The study defined a billionaire as someone with a net worth of US$1 billion or more. It counted individuals, as opposed to families, who have direct control and access to their wealth. It categorised them geographically based on where their primary businesses are held. "The centre of gravity has shifted from West to East," Rambus said, adding that there would be more billionaires in Asia than in North America by 2018. Billionaires in every region have been increasing their wealth, but it has grown fastest in Asia, up 12.9 per cent in the past year. The report predicts that the global billionaire population will increase by 1,700 individuals to 3,900 by 2020. Europe, which has 766 billionaires with an aggregate net worth of US$2 trillion, is still home to the largest number of the ultra-wealthy. By country, however, the United States has the most billionaires - 515 - three times more than second-placed China, which has 157. Germany, with 148 billionaires, is third. Women make up almost 13 per cent of the billionaire population, with 280 women holding aggregate wealth of US$1 trillion. Women tended to inherit their wealth - 71 per cent said their fortunes had been passed down. A further 17 per cent were self-made and 12 per cent were a combination of inherited and self-created wealth. The popular pastimes for high rollers were listed as art, aviation, real estate, travelling and golf.