I can tell you about a different approach,
Just make an NPE with an attribute Count(int).
Put that dataview where you want to show the data, and set its data source to microflow,
Now in the microflow, make an Integer Variable,
and use retrieve and List aggregate(Count) activities to count all the list and then,
use a change variable to change your integer variable as $count1+$Count2+$Count3 and after that,
Use a create activity to create the NPE and set its Count attribute to Variable and then return it.
Hope it helps!
I have achieved this with this microflow I have passed he object through at the end and displayed a text parameter which has a data source of the microflow.
toString($Count + $Count_1 + $Count_2)
Go Make It