volume as a % of avg up to that time of day
Add the ability to calculate how much below or above the current volume is (throughout the day) vs. the average volume over a certain time span in the past up to the same point in time of the day. Example: today up to 10am a stock has traded 100k shares but the average for the last 50 days has an average volume, up to 10 am, of only 20k shares.
Howard Beckett commented
I was going to submit this as an idead I called Implied Intra-day Volume (IIV). Since there are 390 minutes in a normal trading day, take 1/390 of the 50 day Avg. Volume multiplied times the number of minutes elapsed so far that day began and you have the IIV. You would then be able to compare the day's actual volume to the IIV and spot stocks that have jumped way aheadof normal sales early in the day. At the end of the day you can compare the day's volume with the average and see that you had a big day. However, it's more important to spot this kind of move at 10:00 or 11:00 than at the end of the day.