Relative volume (RVOL)
Today's volume compared with a normal day's, adjusted for the time of day.
Formula
RVOL = Volume so far ÷ (Average daily volume × Share of a day's volume usually traded by now)
How to read it
1.0 is a normal day; 3.0 is three times the usual activity — something is going on.
How to use it
Shows when something unusual is happening in a name — news, a breakout, a large holder trading.
Limitations
Early in the session a time-of-day profile is assumed, so a slow open can read low.
In Kereon
Market. Average daily volume is the last 20 sessions. Before the open, premarket volume is compared with 1.5% of it.
Investing · price record. The last session's volume ÷ the 20-session average, with no time-of-day adjustment.
Charts · Superchart. Each bar's volume ÷ the average of the 20 bars BEFORE it, so a spike is measured against what preceded it; a line at 1.
Also called: rvol, rel volume, relative volume, rel vol.