Hi @tonysimonsen,
Alright, thanks for the added context. The deal inactivity property isn’t a default deal property so we’d have to build that first. The approach here would be creating a Today’s date property. Once this property is created, you could use a calculation property to calculate the time between Last contacted and Today’s date. The resulting calculation property could then be visualized in a custom deal report (= a report that shows the calculation property average per current deal stage).
This would only work for the current deal stage, it would not show you historic information of inactivity in previous stages. That would require intricate date stamping and distinct calculation properties for each stage which could not be displayed within one report.
Hope this helps!