Use data from all devices in 1 group in the dashboard

Hi Team

I have several devices within 1 Group or Asset Type and these sensors have all the same bucket lay-out.
Now, we have a dashboard to visualize the content of individual device buckets. But we want to visualize the same content per group of sensors. So when we have different devices per building measuring the waterflow, we want to show the total waterconsumption of all devices in that building. All sensors of that building are then in the same group. How is (or will) this (be) possible?

Via the source switcher, we cannot select groups or multiple buckets.

Will we need to create a bucket per group?
Other things being developped?

Kind regards
Gus