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Excel Grand Total Not Matching My Average
Having an issue with grand total from a pivot table, this is in a data model btw with relationships between tables.
How does excel calculate Grand Total %? because if you do the average of the weeks from 10 to 14, it's not 87.50%.
Another example below, shouldn't it be 84.6? what am i not understanding about Grand Total %?
1 Reply
Here is a very simple example:
The average for F25-13 is 100% and that for F25-14 is 20%.
But the overall average is (100%+20%+20%+20%)/4 = 40%.
In other words, the average over all weeks is not the same as the average of the weekly averages, since the number of data points can vary from week to week. If the number of data points is the same for each week, the overall average would be equal to the average of the weekly averages:
