Measure calculation using row context

Hi;

I am try to calculate a measure NumDaysOpenShop, in a Period Year/Month and in a Shop or in all shops 

LIke page filters i have got a Year and a Shops, in the year i can select only one, in the shop i can select one, some or all shops. 

In matrix i show year/month on rows

2022                             Measure be SUM([Table][Colum]) with dates in 2022 and shop selected in page filter, except if all or more than one shop is selected, in this case i want use MAX(measure [NumDaysInMonth] with dates in 2022   

   January                      SUM([Table][Colum]) with dates in January 2022 and shop selected in page filter, except if all or more than one shop is selected, in this case  i want use MAX(measure [NumDaysInMonth] with dates in 2022   

Hope i explained 

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