Since last Friday, shares of the digital audio company Sirius XM Holdings (NASDAQ: SIRI) are now trading 13.5% lower as of 1:52 p.m. ET Thursday. Sirius, a stock Warren Buffett's Berkshire Hathaway has been piling into,

Warren Buffett urges investors to see downturns as opportunities rather than reasons to panic, according to an op-ed the billionaire wrote in 2008. Buffett has long emphasized that bad news creates discounted buying opportunities for those who focus on value over short-term price swings.

It wasn’t just Apple shares that Buffett-led Berkshire Hathaway sold last year. The company also cut its stake in Bank of America by 34 per cent. Since then, Apple and Bank of America have seen their share prices decline by 15 per cent and 20 per cent respectively,

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