A down-bar whose volume is lower than the volume of the previous two bars (or low relative to the 20-bar average), showing that professional selling is absent as the market falls. It is the simplest of the strength signals—purely a volume observation—and works best when there is already strength in the background, or following a minor sign of weakness within an established uptrend. The next bar should be up; in an uptrend, expect continuation, while in a downtrend it may only produce a temporary pause.