As a Confluence Administrator, you can decide which file types (Microsoft Word, Excel, Powerpoint, PDF, Gliffy, Images, etc.) you would like to track. You may want to track very specific file types only to keep the Report "clean".
In the Attachment Report, click on "Settings".
You are presented with a list of file types that are currently tracked.
Click on the list to add or remove file types. The changes will be saved automatically.
The Attachment Report will now show the file types you have selected, starting today.
Note: Existing attachment views (collected before the settings were changed) will remain in the database and will not be deleted. They might show up in the Report.