United States Billionaire count: 480 Total wealth: $2.05 trillion The United States still leads the world with its billionaire tally, far outpacing its closest competitor China with a whopping 333 more billionaires. Despite the economic headwinds, the U.S. minted 25 new billionaires in the past year -- a 5.5 percent increase from the previous year. Their combined wealth also grew nearly 8 percent from the previous year to $2.05 trillion. American billionaires account for less than 1 percent of the ultra-rich population, but control nearly a quarter of the group’s total fortune of $8.28 trillion. On average, these billionaires are worth $4.3 billion each. The country’s ultra-rich saw a more than 3 percent increase in wealth, while the group’s population grew by nearly 4 percent, compared to last year — outpacing U.S. GDP growth. California is the number one state for the ultra-wealthy, followed by New York, Texas, Florida, and Illinois. A major driver of wealth for the ultra-rich was the U.S. equity markets, with the S&P 500 index up over 7 percent between August 2011 and July 2012. As a result, 2,250 people joined the ranks of the ultra-rich club in the past year. Despite the fast pace of growth in America’s ultra-rich numbers, Wealth-X projects that Asia’s ultra-wealthy population will surpass that of the U.S. by 2025, while their combined wealth will overtake them by 2020.