Apple revenues miss expectations despite high sales figures
24 January 2013 Last updated at 09:28 GMT
Apple reported another set of record sales figures on Wednesday. The tech giants sold 47.8 million iPhones and 22.9 million of its iPad tablets.
But despite the numbers, investors were still disappointed. In after-hours trade, shares slumped another 10%, wiping $50bn off its value, after what has been a tough few months for the firm.
The BBC's Ben Thompson investigates what has worried the markets.