This can be hard to wrap your mind around, but the simple fact is that a price drop (or rise) on little volume is not a strong signal. A price drop (or rise) on large volume is a stronger signal that something in the stock has fundamentally changed. Read more: http://www.investopedia.com/articles/technical/02/010702.asp#ixzz1Pq0VkfVZ Bottom line: High volume with a dropping PPS is not good.
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