$1,000 a minute: That's what the richest earn in US

New Delhi: How do you define richness in America? Well, it's quite tough to arrive at a definition. But all one knows is that one needs to be worth at least $1.3 billion to be among 500 richest people in the US. Or that is what the new rich list of the Forbes magazine suggests.

And this income, according to Forbes, adds up to quite a hefty salary every minute. To make the math easier, this year Forbes even calculated just how quickly these billionaires make their money.

For instance, it takes Oprah Winfrey just 30 seconds to make $1,000. She's ranked 165 on the list.

But Microsoft founder Bill Gates continued to be the wealthiest American for the 14th straight year with a net wealth of $59 billion. He was closely followed by investor Warren Buffett in the list.

Giving the names of 400 richest people in the US, Forbes reported that Gates and Buffett added six billion dollars each to their net worth. Buffett, with $52 billion, has pledged 85 per cent of his net worth to the Gates and Melinda foundation and family charities.

Turmoil on the Wall Street failed deter the richest from getting rich and total net worth of the America's mightiest plutocrats rose $290 billion to touch 1.54 trillion in a year.

But an interesting statistic is that a billion dollars now does not guarantee a ticket to the rich list and minimum requirement to enter is $1.3 billion.

Nearly half of the 45 new members made their fortunes in hedge funds and private equity. Money manager John Paulson joins the list after pocketing more than one billion short-selling subprime credit this summer.

The youngest among the billionaires is hedge fund manager John Arnold, 33, who is ranked 317 with net worth of $1.5 billion. But the 214th spot finds the oldest among the richest in the US - John Simplot, who is 98 years old and has a fortune of $3.6 billion.

Sheldon Adelson, 74, who heads the Las Vegas Sands with a worth of $28 billion and Chief Executive of Oracle Corp, Larry Ellison with a fortune of $26 billion remain at third and fourth position. But interestingly, the net fortune of Adelson is nearly half of Buffett who is at the second position.

Google co-founders Sergey Brin and Larry Page occupied fifth position with net worth of $18.5 billion each.

Investor Kirk Kerkorian, whose business include casino, added nine billion dollars to his wealth last year to reach $18 billion and occupy seventh spot followed by Michael Dell, Chief Executive of Dell Inc, the second largest PC maker, with a net worth of $17.2 billion.

Forbes estimated that Kerkorian added maximum wealth among the billionaires to his fortune last year.

Closely following Dell were brothers Charles and David Koch with a net worth of $17 billion each.

Leveraged buyout titans David Bonderman and James Coulter of Texas Pacific Group make their first appearance on the list, along with William Conway, Daniel D'Aniello and David Rubenstein of the Carlyle Group.

Twelve people returned to the list, including computer memory mavens David Sun and John Tu.

Fifty people couldn't keep up. They include online gambling titans Ruth Parasol and J Russell DeLeon, whose PartyGaming Internet poker company's stock has fallen 75 per cent in the past 12 months. Also dropping off the list is caffeine king Howard Schultz, whose Starbucks, Forbes said, has languished over the past year, and Campbell Soup heir Dorrance Hill Hamilton, who had appeared on every Forbes 400 list since 1982.

(With inputs from Agencies)