Warren Buffett’s really bad week

Three of billionaire investor Warren Buffett’s biggest investments took a downturn this week, posting a $1.2 billion total loss for the Oracle of Omaha.

After a prediction this week of flat sales in 2015 and declining sales for the next two years, some 60.4 million shares of Wal-Mart Stores Inc. (NYSE: WMT) held by Buffett’s Berkshire Hathaway Inc. racked up a $360 million dollar loss for the Omaha, Neb.-based holding company.

Berkshire's portfolio lost roughly $170 million of an estimated $24 billion stake in Wells Fargo & Co. (NYSE: WFC) when the banking and financial services company reported 1 percent earnings. Berkshire’s investment portfolio holds 40 million shares.

International Business Machines Corp. (NYSE: IBM) was the third and largest hit, losing $680 million on Berkshire’s nearly 79.5 million shares when the tech company reported earnings in the third quarter were 14 percent below last year.

Although the three companies, along with American Express Co. and Coca-Cola Co., make up 60 percent of Berkshire’s stocks, the week’s losses amount to a roughly 1 percent loss for Buffett’s $115 billion portfolio.

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