53 New Yorkers among richest 400 Americans, with Bloomberg near the top

Mayor Michael Bloomberg's fortune grew to $25 billion over the last year, making him the second-richest person in New York City and the 10th richest in the country, according to Forbes' annual list of the 400 wealthiest Americans.

Fifty-three New Yorkers made the list, representing about $230 billion in wealth. The mayor's wealth rose by $5.5 billion thanks to the success of his corporation Bloomberg L.P., bumping him up two slots in the rankings.

With a staggering $66 billion fortune, Microsoft honcho Bill Gates was No. 1 for the 19th straight year.

Other famous city billionaires on this year's list include David Koch ($31 billion), Rupert Murdoch ($9.4 billion), Donald Trump ($3.1 billion) and Mort Zuckerman ($2.4 billion).

Overall, the combined wealth of the 400 is $1.7 trillion, up from $1.5 trillion last year, which Forbes attributes to a rising stock market, rebounding real estate values and rising values for art works.

Though the overall trend was upward (average worth of the 400 is around $4.2 billion, up from $3.8 billion last year), there were a few notable drops this year. Facebook founder Mark Zuckerberg visibly lost huge amounts of money when Facebook's share price plummeted, and his net worth fell by nearly half to $9.4 billion, putting him at No. 36 this year.

Here are the 10 richest New Yorkers, according to Forbes:

1. David Koch, $31 billion

2. Michael Bloomberg, $25 billion

3. George Soros, $19 billion

4. Cark Icahn, $14.8 billion

5. Ronald Perelman, $12 billion

6. John Paulson, $11 billion

7. James Simons, $11 billion

8. Rupert Murdoch, $9.4 billion

9. Leonard Lauder, $7.7 billion

10. Sam Newhouse, Jr., $74. billion