change volume to average is value 1, positive volume would be green +, neg-red -, would alert to volume indications and changes.
the current number in the volume column does not alert the user on a visual scan that volume activity may be higher or lower than the market in general. I can miss a market move in price that could have been detected by volume change. There are other indicators, and I quess your rt comes the closest. I would prefer a simple red or greeen, based on average volume with a value of 1, and the next column and number is green and positive, or red and reflects less volume.