What’s happening to Apple’s share price?

Last night Apple's share price declined to $392.05, wiping 44.16% or $310.05 of the value of each AAPL share since September 2012 (the stock closed at $702.10 on 19 September), and dropping to its lowest level since December 2011. In the first quarter of the year Apple was one of the worst performers of the S&P 500 in what is being described as a crisis among investors.