Dynamic monthly MAX depending on slicer selection

Hey all,

I'm struggling to find a solution in order to calculate a measure which provide the cusmized Max I need. In particular, I need the monthly max for each Division to show it in a graph, but i also want to get the maximum considering more than one division (that i choose on the slicer).  Example below: I want power BI to calculate what the sum of daily sales for division A and B and provides the max for each month. 

I managed to calculate the max per monthy for each division by creating a column, but it does not allow me to provide customized maximums depending on what I select.

Please find there the .pbix and the excel and let me know if you know how to do it!

Thanks!