Creating a simple calculation
Procedure
 Select the items in the report to calculate.

In the report object toolbar, click the insert calculation button and select the calculation to perform.
Tip: Calculations that are not applicable to the items you selected are grayed out.
In addition to simple arithmetic calculations, you can perform the following calculations:
Calculation
Description
Rollup
Summarizes, or rolls up, all the values of the selected items in a hierarchy.
%
Calculates the value of a selected item as a percentage of another item.
% Difference
Calculates the difference between two items as a percentage.
% Of Base
This calculation is only available if you select two members from different hierarchies, each from a different edge.
This calculation takes the first selected member from edge A and the second selected member from edge B. The calculation result of a percent of base should be such that all the values for member A will compare itself to the intersect value of member A and B.
For example, you have a crosstab showing quantity sold by year by product line. You select the current year and Camping Equipment, rightclick the selection, click Calculate, and then click % of Base (currentyear, Camping Equipment). The calculated row shows the percentage value of each product line for the current year as compared to Camping Equipment for the current year.
Custom
Allows you to specify your own value when performing a simple arithmetic calculation. Also allows you to change the order of operands or type a custom name for the new calculated row or column.
 To change the order of the operands or the name of the calculated item added to the report, click Custom.