Hi @fabdata1207 ,
A calculated column is static, it won't change for slicer selection.
You may try a measure instead.
First you need to create a separate country table for the slicer to select. This country table cannot have a relationship with the main table.
A calculated table:
Then, create a measure.
Total Dynamic Measure = CALCULATE(SUM('Table'[Value]),FILTER(ALLSELECTED('Table'),[Country] in ALLSELECTED(Country[Country])))
You can check more details from the attachment.
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