Buffett Watch

Warren Buffett's Hot January: Berkshire Up 17.5% Over Two Weeks

Shares of Berkshire Hathaway soared a blazing 17.5 percent over the last two weeks of January, putting Warren Buffett well ahead of the benchmark S&P 500 that he'll be joining soon.

A fifty-for-one stock split for Berkshire's Class B shares, and the subsequent announcement they will go into the S&P to replace Berkshire acquisition Burlington Northern Santa Fe, helped fuel big gains for the Baby Bs.

They advanced on six of the nine trading days (the market was closed Monday, January 18 for Martin Luther King Jr.'s birthday observation).  The smallest daily gain was 2.6 percent on January 19.  The biggest advance: 5.2 percent on January 27.

For January (and the year-to-date, of course), Berkshire Bs are up 16.3 percent, significantly outperforming the S&P's 3.7 percent drop.

The stock is now at its highest levels since Halloween, 2008.

Current Berkshire stock prices:

Class A:

Class B:

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