Apple dumps $158B, enters bear market

Shares of Apple are getting crushed again Friday, falling $6.72, or 6%, to $106.02. The stock is now down a bruising 8.5% just this week - making it an even worst performer in an ugly stock market.

The fate of Apple is more than a story of single stock. Apple is the the stock that captures if not personifies this bull market. It's a top holding by individual investors - many of whom are new in the market. Its shares have benefited from the mobile data boom, which fueled much of the bull market. And Apple's enormous profit margins and surging record cash pile are a testimony of the company's ability to command premium pricing for its products - and consumers' willingness to pay up.

But the same factors that made Apple so important during the bull - makes it the key stock to watch as the market unravels. The Apple stock crash is reaching proportions that are downright ugly - breaching three important levels that quantify just how this isn't your typical decline.