i can only guess but look what happened last earnings 4/24; it gapped the next morning and ran hard for two days (45 - 62.5); short interest may be as high as 15% of float; i wonder if many shorts were not added today in the gloomy tape; also, big earnings tomorrow - AAPL, BIDU;
it traded in a box of approximately 75-76 to 67-66, so first measurement BO equals roughly 84ish; thats were it is trading now AH; the yahoo AMZN board is full of people anxious to short