WorldCat Discovery manual

You can select to keep track of the books and other items that you have borrowed previously. This way you can go back in time to see which books you have previously used for your research. This history is only stored in your account, it is not visible to library staff or other users.

Go to the Profile tab in My Account and turn on Enable my borrowing history. Now, each time you return a borrowed item it will be added to your history. The borrowing history saves returned items up to a maximum of five years.

To stop tracking your borrowing history simply turn off the Enable my borrowing history setting. This will also delete the existing history.