There are now 313 billionaires in the country, the largest number ever and a huge jump over the 262 counted last year, according to Forbes magazine, which Thursday released its annual ranking of the 400 richest Americans.
The combined net worth of the 400 rose $45 billion and reached $1 trillion this year for the first time since 2000, before the dot-com bust wiped out billions of dollars in wealth.
The biggest billionaire of all was again Microsoft Corp. founder Bill Gates, whose $48 billion in estimated wealth was up $2 billion from 2003. Gates was again followed by investor Warren Buffett with $41 billion, the list's biggest dollar gainer with a $5 billion increase, and Microsoft co-founder Paul Allen, who held the No. 3 spot although his net worth fell $2 billion to $20 billion.
Members of the Walton family, whose fortune comes from Wal-Mart Stores Inc., again swept spots four through eight, with each having estimated wealth of $18 billion.
The only tweak in the top 10 from last year came from Dell Inc.'s Michael Dell and Oracle Corp.'s Lawrence Ellison, now No. 9 and No. 10 respectively after swapping places from 2003. Dell stock has weathered the tech slump relatively well over the past year, giving Michael Dell a net worth of $14.2 billion. Ellison, whose stock has suffered, had $13.7 billion in holdings, a drop from $18 billion last year.
There are 45 new names on the list, including Google's Sergey Brin and Larry E. Page - also the youngest members of the 400 at 31. The two tied for No. 43 with $4 billion each after their company's stock went public in August.
Forbes senior editor Peter Newcomb attributed the overall gains in the list to the improving economy, as well as a good year in the financial sector and industries including food and wine.
Casino mogul Steve Wynn, who climbed to No. 215 from No. 377 last year, saw the largest percentage increase in wealth - a 100 percent jump to $1.3 billion from $650 million. Last year's biggest dollar gainer, Amazon's Jeff Bezos saw his net worth fall by $800 million.
Donald Trump's net worth edged up $100 million to $2.6 billion, despite the financial problems of his casino empire. But Trump slipped three spots on the list, falling to 74 from 71.
Returning to the list after a year's absence was Teresa Heinz Kerry, wife of Democratic presidential nominee John Kerry. Teresa Heinz Kerry's $750 million in wealth tied her for last place.
Fifty-four people dropped off the list from last year, including such notables as Disney's Michael Eisner, BET's Robert Johnson and Monster.com's Andrew McKelvey.
The 400 list includes 51 women - up just one from last year, but the average net worth of the women is $2.8 billion, higher than the list's average of $2.5 billion.
Only 50 names remain of the original 400 from the list's debut in 1982. While some died or divvied up their assets, more than half were simply surpassed.
And while New York City still claims the most 400 list members per city with 38, the state of California, with 98 members, again outdistanced the state of New York, with 49.
"There's been a huge shift from east to west, and that trend is not slowing down at all," Newcomb said.
Forbes compiled its list by estimating the value of stock and other assets such as real estate held by the wealthiest Americans, Newcomb said. Forbes used the stock prices of publicly held companies as of Aug. 31; for privately held companies, the magazine estimated a fair market value based on the stocks of their publicly traded peers.
If the economy continues its upward trend, it's likely the 400 will grow even wealthier, Newcomb said, adding, "It won't be too long before our entire list consists of billionaires."
By Madlen Read