After Losing Billions, Is Warren Buffett Still the World's Richest Billionaire?

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Warren Buffett has certainly lost billions of dollars over the past year, but has he lost his title of "World's Richest Billionaire?"

We'll find out when the 2009 edition of the widely-followed Forbes ranking of global wealth is released at 6p ET tonight (Wednesday).

Based on my own extremely back-of-the-envelope calculations, Buffett will still be number one with an estimated fortune of about $40 billion. That's down from the Forbes estimate of $62 billion a year ago.

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Microsoft's Bill Gates, last year's #3, will be down from $58 billion to around $34 billion.

And Mexico's Carlos Slim, number two in 2008 with $60 billion, will see his wealth drop to the low $20s of billions.

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My method is no more scientific than calculating how much shares of Berkshire Hathaway (down 37%), Microsoft (down 41%), and Telmex (down 60%), have fallen over the past 12 months.

Forbes, of course, will do a much more thorough job.

Current stock prices:

Berkshire Class A:

Berkshire Class B:

Microsoft:

Telefonos de Mexico:

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Questions? Comments? Email me at buffettwatch@cnbc.com