Show each row's share of the column total, then format as a percentage.
Copy this formula
=B2/SUM($B$2:$B$100)Divide each value by the total of the whole column. Lock the total range with absolute references ($B$2:$B$100) so it doesn't shift as you fill down. Format the result cells as Percentage.
=B2/SUM($B$2:$B$100)→18%This row is 18% of the total.
The math is right; the cell just isn't formatted. Apply Percentage number format (Ctrl+Shift+%).
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