Bearish momentum divergence seen on PFE via the Mac-D histogram. As one can see, PFE tends to follow these divergences quite cleanly and trades back to the 50 EMA. All of these reference points are taken from the Bollinger Band extremes. The first lower/higher reading on the histogram has spelled reversal in the past. Today, our histogram has put in it's first lower high signaling an entry. Conservative traders may look for a break of today's low to enter short. I'm looking for price to gravitate back towards the 50 ema.