The report settings, accessed from Store » Configuration » Reports (/admin/store/settings/reports), control a few aspects of the reports that Ubercart generates. Note that this tab is only available if you've enabled the optional uc_reports module that comes with Ubercart.
Number of rows to show in reports
This will set the maximum number of rows used on every report page. Depending on your server hardware, store size, and screen visibility, you will want to adjust this value accordingly.
Reported status
These are the order statuses that will be used in reports dealing with sales numbers. You can select multiple statuses. For more about order statuses, see ...