They represent small price/volume horizontal histograms,inside each day. Thus, a fat fin indicates a zone of congestion, in which many trades took place, at a respectable volume. Today we had 2 major crowded zones with their peaks (75.71 and 74.90) marked on the chart. In addition, 3 minor zones of congestion can be detected. This indicates a strong, move downhill, which occurred in successive waves of action. But…is this action sustainable???