volume bar velocity indicator

[adryden]

i have done a few searches for such a beast, but have not found what i am looking for. and i hope i am articulating well what i seek.

does there exist anywhere an indicator to track the relative velocity of trades within individual volume bars? for example, say i have a 500v chart and wish to monitor the velocity of transactions vis-a vis a certain timeframe..or perhaps just vis-a-vis a certain sample of previous volume bars.

hope this query makes sense.
thank you,
angela

[adryden]

maybe a ROC for volume?

maybe what i am looking for is a Rate of Change indicator for volume.

would really appreciate any feedback.
thank you,
angela