You need to create a microflow that based on the two dates retrieves all the objects between those dates and then iterate over those to create the data for your charts. I would use a non persistent object for that.
Regards,
Ronald
Thanks for your quick response.
Unfortunately I'm still a Mendix beginner, so maybe you can briefly explain to me how I build the microflows based on the two dates?
I would then try to solve the next steps by myself.