Report Builder has access to a number of Aggregate Functions. These allow for the summarisation of data in the reports to better suit our needs.
The Aggregate functions can be entered in any cell directly below a column – including the cells of Group By rows. If a function is entered in the very bottom cell (the row without a Group By) then it will perform that function on the entire report.

The available options will differ depending on the type of column.

Text based cells have use of the following functions:

Count
First
Last
Distinct
Expression

Numerical based cells have access to the above plus the additional functions of:

Total
Average
Minimum
Maximum

To use these features, select Design View and right-click on the relevant cell (not the header). A sub-menu will appear allowing you to select the function you would like to use.
To remove the function, right-click on the relevant cell and un-tick the option in the sub-menu.

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