Warren Buffett's Berkshire Hathaway posted its worst performance since the famed financier took over the company in 1965.
The company posted a $117 million quarterly gain - a 96% drop from last year's $2.95 billion fourth-quarter income. It also reported a 9.6% loss in book value.
In his annual letter to shareholders, Buffett admitted to doing some "dumb things," such as buying shares in oil giant ConocoPhillips at the peak of the boom and investing in high-flying Irish banks that later stumbled.
He also filled his letter with folksy sayings, for which he is famous. For example, in speaking about the insurer GeneralRE exiting the complex derivatives market, he said:
"Upon leaving, our feelings about the business mirrored a line in a country song: 'I liked you better before I got to know you so well.'"