Mad props to savvy trader Michelle B, who passed along this relative volume tool from James de Porre and the Shark Investing site. The charts track both NYSE and NASDAQ volume; in blue you can see how the most recent day's volume has shaped up with respect to the past X days, with X going from 5 to 50. During the trading day, yellow bars show how the day's current volume is shaping up relative to the volume at that time of day for each of the prior days. There's a 20-minute delay on the data.
Great data catch by RevShark; much more on his site as well.
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