# Create a Simple Member Calculation

When working with dimensional data sources, you can select members in your report and create simple calculations.

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 2012 and Camping Equipment, right-click the selection, click Calculate, and then click % of Base (2012, Camping Equipment). The calculated row shows the percentage value of each product line for 2012 as compared to Camping Equipment for 2012. |

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. |