Any item in a report can be defined as “the sum of the items above it”. This means that you don’t need to specify the formula directly. Also, as you add or remove items above it, the item will change just like a SUM function in Excel.

To make say [Gross Profit] into a sub-total, right click on it and choose “Sum of above”. You will see that it becomes bold. If you right click and choose “Sum of above” again, it will go back to a normal report line.