Now, being a billionaire not enough to make Forbes list

NEW YORK - A billion dollars just doesn't go as far as it used to.

For the first time, it takes more than $1 billion to earn a spot on Forbes magazine's list of the 400 richest Americans. The minimum net worth for inclusion in this year's rankings was $1.3 billion, up $300 million from last year.

The new threshold meant 82 of America's billionaires didn't make the cut.

Collectively, the people who made the rankings released yesterday are worth $1.54 trillion, compared with $1.25 trillion last year.

The very top of the list was unchanged: Microsoft Corp. founder Bill Gates led the list for the 14th straight year, followed by Warren Buffett of Berkshire Hathaway Inc. in second place and casino mogul Sheldon Adelson at number three.

Larry Ellison of Oracle Corp. maintained his fourth-place ranking with an estimated net worth of $26 billion.

Joining the top 10 for the first time were Google Inc. founders Sergey Brin and Larry Page, who tied for fifth place.

And, lower down, almost half of the 45 newcomers made their millions in hedge funds and private equity investments. The youngest member of this year's list was 33-year-old hedge fund manager John Arnold, who joined the ranks at number 317 and a net worth of $1.5 billion.

"Wall Street really led the charge this year," said Matthew Miller, editor of the Forbes list. "God only knows if they'll be on it next year. It really just depends on what the market does."

Surging oil prices also helped oil baron brothers Charles and David Koch break into the top 10, sharing the number nine spot with an estimated $17 billion. They bumped the Walton family, heirs to the Wal-Mart Stores Inc. fortune, from the top 10 for the first time since 1989.

The discount retailer has seen its sales lag behind rivals like Target Corp.