If you'd like to clean up the My Book Reports section on your Dashboard, you can easily do so by archiving your old reports!
Here's how to archive a book report:
Navigate to the Dashboard.
Under the My Book Reports section, hover over the book report.
Select the file bin icon to archive the report.
Click Yes, Archive This Book Report button.
Note: Archiving your book reports only removes it from your dashboard; it will not be deleted from the system.