Recession or no recession - America's super-rich got even richer this year. Forbes Magazine has released its inaugural list of the 400 wealthiest people in the country. More than half of those on the list added to their fortunes this year. Microsoft chairman, Bill Gates, held the top spot for the 17th consecutive year.

Bill Gates has famously pledged to give at least half of his fortune to philanthropic causes. And that's looking like a hefty donation. The richest man in the U.S. boasts assets estimated at around 54 billion U.S. dollars, up 4 billion dollars from last year.

Number 2 on the list is investor and fellow philanthropist Warren Buffett. He's now worth 45 billion dollars, up 5 billion from the year before. Oracle founder Larry Ellison's net worth was unchanged at third place, at 27 billion.

With a net worth that grew by nearly 4.9 billion dollars, Facebook founder Mark Zuckerberg had the largest percentage gain this year. He jumped from 158th to the 35th spot, with a fortune of 6.9 billion dollars.

There are 16 newcomers on the list this year, including 26-year old Dustin Moskovitz. The Facebook co-founder is the youngest billionaire on the list.

And 42 women made it onto this year's list, led by Wal-mart heir Christy Walton at fourth place, with 24 billion dollars.

California had the most billionaires on the list, with 83, followed by New York, with 64, Texas had 45 and Florida had 26.

The surge in wealth for America's financial elite is in stark contrast to last year's list, which saw over 300 of the country's richest 400 individuals see their fortunes shrink.