The ordering is designed to let you control how a report sheet orders when its reported. This works on single page reports as well as grouped summary reports.
To set it up you will need to go to the sheet designer and open the output sheet. There is a new button called Output Options on the Design ribbon.
The window above shows the ordering window in the output options. You will be able to move any of the available values across to the selected column and the output will be ordered by those values.
You can have more than one option in the selected column. The order in the selected column is the priority order which will be used.
The example above will order by the location ID then the top depth.