In a report studio crosstab often we have some measures and a percentage for that measure.
When you add totals to the crosstab, the column of the percentage is also being totalized. But this is not the right way. For the percentage we want the average instead.
Go to the query on the crosstab.
Look for the item that represents the total.
This item has the expression: total(currentMeasure within set [Region])
Change this expression to: aggregate(currentMeasure within set [Region])
Run the report again to see the difference