Dynamic Group By
You can use Dynamic Group By to group report results by different columns depending on which parameter the user selects when running the report. Dynamic Group By uses an if-then-else expression that evaluates the selected parameter value to determine how to group the data.
For example, if you have a list with Column A, Column B, and Column C, you can add a fourth that groups the results. When running the report, the user selects one of the columns as a parameter. If the user selects Column B, the results are returned to the user as a list that is grouped by Column B.
To hide the Dynamic Group By column in the report results, set the column Render property to No.