Sum calculation on virtual column of a Group aggregate

[Johnny_Hacking]

I need some help on how to do this. Right now we have an inventory app that has each piece of equipment in it has a quantity and value. I am using a virtual column that displays the total value by times the quantity by the value to show what the total value of that item would be. In my table view I am grouping it by location (each item is assigned a 1 location out of 6) and then do a Group aggregate with a sum of the total value of each location. This works great! My question is how do I show a total value of all those sites combined?

thanks,