How to Sum/Calculate Total Values with Duplicate Values Only Once in Excel
In statistic when calculating the total values for a range of numbers, we often count duplicate values only once. Normally, if only apply SUM function to calculate total values, it will cover all values including all duplicate values. So, we need to update the formula to make it meet our requirement. This free tutorial will show you the formula to sum values with duplicate values only once in the selected range.
Precondition:
See screenshot below. We want to sum all values but for the duplicate values, we only count once.
Method: Calculate Total Values with Counting Duplicate Values Only Once
Step 1: In B7, enter the formula =SUMPRODUCT(A2:B6/COUNTIF(A2:B6,A2:B6)). In this formula, A2:B6 is the range selected for calculating.
Step 2: Click Enter to get result. Verify that the sum value is calculated properly. Duplicate values like 100, 60 are only count once.
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