Why do $UVOL and $DVOL decrease during the day?

[Dave180]

$UVOL and $DVOL do not act as I expect. Like a cumulative total volume plot I expected the Up and the Down volume to increase and never decrease during the day, on the basis that a trade in a stock adds volume to either the Up, the Down, or the Unchanged total, but never subtracts from any of them.

How can any of these totals (as opposed to Up - down say) ever decrease, as shown in at various times on a 3min plot over the last few days

Thanks

[ACM]

Re: Why do $UVOL and $DVOL decrease during the day?

Dave180
You can find the explanation in this article of the eSignal KnowledgeBase
Alex

Originally posted by Dave180
$UVOL and $DVOL do not act as I expect. Like a cumulative total volume plot I expected the Up and the Down volume to increase and never decrease during the day, on the basis that a trade in a stock adds volume to either the Up, the Down, or the Unchanged total, but never subtracts from any of them.

How can any of these totals (as opposed to Up - down say) ever decrease, as shown in at various times on a 3min plot over the last few days

Thanks

[Dave180]

Thanks Alexis, not quite what my mental picture was, I had thought it was more like a cummulative Tick of volume split into up and down tick vol counts. I can't quite figure what the "meaning" of moving volume from one total to another is.