Hi @Mohannad17 ,
If the Summarization of Population column is Sum, and in the Values pane, Sum is selected in the Population column drop down options, the Population column will automatically add in the visual.
Or only select Sum in the Values pane in also OK.
Or replace Population column with a measure:
Sum = SUM('table'[Population])
I attach my sample below for reference.
Community Support Team _ kalyj
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