Warren Buffett's Berkshire Hathaway may have suffered $70 billion in coronavirus losses on its 10 biggest investments

• Warren Buffett's Berkshire Hathaway probably suffered $70 billion in losses on its 10 biggest equity holdings during the coronavirus-driven market sell-off.
• The value of Berkshire's stakes in Apple, Bank of America, and other blue-chip stocks dropped by an average of 37% between February 20 and March 10.
• Berkshire took a $20 billion hit from Apple's stock-price decline, and a $14 billion hit from Bank of America.
• Its worst performer was Delta Air Lines, down 58%, while Kraft Heinz stock fell only 14%.
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Warren Buffett's Berkshire Hathaway probably recorded about $70 billion in losses on its 10 biggest equity investments in the past month. The coronavirus-fueled market sell-off decimated the value of its shares in Apple, Coca-Cola, Delta Air Lines, and other blue-chip companies.

The famed investor's conglomerate saw its top 10 holdings suffer an average drop in share price of 37% between February 20 and midday March 18. These figures assume Berkshire hasn't tweaked its portfolio since disclosing it for the end of December.

Apple's stock price tumbled about 24% in less than four weeks, slashing the value of Berkshire's 5.6% stake in the iPhone maker by about $20 billion. Bank of America's stock plummeted 43% over the same period, wiping close to $14 billion off Berkshire's investment in the lender.

Berkshire's stakes in American Express, Wells Fargo, and US Bancorp shrank in value by more than 40%. Its shares in Moody's and JPMorgan Chase, down more than 38%, weren't far behind. The worst performer was Delta - the airline's stock price dived 58% as travel restrictions and fear of flying hammered demand.

Berkshire's Coca-Cola shares tumbled a hefty 29% as well. Surprisingly, its Kraft Heinz investment was the best of a bad lot, sliding only 14%. Investors may be betting the food titan benefits from consumers hoarding cheese slices and ketchup, or they might spy value in a stock that has already plunged more than two-thirds in the past two years.

The overall worth of Berkshire's 10 biggest stock positions dropped from about $208 billion to $138 billion in less than a month - a $70 billion decline. Here's a chart showing the astounding wealth destruction: