You can use several techniques to subtract a percentage from a sum in Excel. The Houston Chronicle elaborates on a simple method that can be used in versions of the software up to MS Excel 2013.

### Calculate the sum

The first step is to calculate the sum with the formula “=sum(cellX:cellY)” entered below the cell range of a sum. For example, the sum for cells A1 to A10 is calculated with the formula “=sum(A1:A10)” inserted into the cell A11.

### Enter percentage to be deducted

The percentage to be deducted from the sum should be entered into the adjacent cell of the sum. In this example case, cell B11.

### Enter final calculation formula

The formula “=cell of the sum-(cell of the sum * cell of the percentage followed by %)” is used to calculate the final result. In the example above, formula “=A11-(A11*B11%)” would deduct a percentage set in the cell B11 from the sum of the cell range A1 through A10.