What it is
Relative volume, or RVOL, compares today's shares traded with the stock's own average. That average usually covers 20 trading days. An RVOL of 2.0 means twice the normal volume. It is the best way to tell whether a move has real participation behind it. A 5 percent gain on half the usual volume means few people took part. The same gain on twice the volume means a crowd changed its mind.
How Breakaway uses it
The VOL trait fires when RVOL is at least 1.5 times the 20-day average. It is the participation trait most people look at first. The Unusual volume list filters the scanner down to stocks at 2.0 or more. RVOL is printed at the bottom of every card, so you get the number and not just the chip.
Volume can confirm a move or come before one. That is why RVOL and its opposite, volume dry-up, cannot both be true. A stock is either quiet or loud on a given day. So the top technical score is 13 rather than 14.
How to read it
High RVOL on an up day with a close near the high is what a breakout looks like. High RVOL on a down day means holders are selling out. High RVOL with a small price change can mark a top, especially after a big run. Buyers and sellers are trading heavily at the same price. Always read the volume together with the bar it came on.