Warren Buffett's Berkshire Hathaway failed to beat the S&P 500's return last year, meaning it missed Buffett's target of beating the index over a five year period for the first time.
Until now the insurer has managed to achieve its five-year target every year since Buffett (pictured) took over management in 1965.
But in 2013, Berkshire Hathaway's book value per share rose 18.2%, while the S&P 500 index surged 32.4% over the same period,
This means that over five years since 2008 Buffett has only managed to achieve a 91% return, while the index increased by 128%, fulfilling analysts' predictions that Buffett would fail in his task.
Annual shareholder note
In his annual letter to shareholders, Buffett wrote: "We expect to fall short in years when the market is strong - as we did in 2013. We have underperformed in ten of our 49 years, with all but one of our shortfalls occurring when the S&P gain exceeded 15%.
"Over the stock market cycle between year ends 2007 and 2013, we overperformed the S&P. Through full cycles in future years, we expect to do that again. If we fail to do so, we will not have earned our pay."
Despite the lesser performance, Berkshire Hathaway still managed to achieve a record profit in 2013: $19.5bn (£11.6bn) versus the $14.8bn made the previous year.
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