Settings
The Settings option lets up to configure the compression and retention for the backup schedule.
Compression
By default, all the backup data is compressed while storing in the backup repository. If disabled the original size of the backup data will be stored.
Retention
Enabling this option lets you specify the number of restore points you want to retain. If disabled, all restore points will be retained.
User Mailbox (Mail, Calendar & Contacts): From the drop-down list select the time to retain. You can choose either days, months, or years.
User Mailbox (Google Drive): You can select both the number of versions and number of days to retain the Google Drive items. The minimum retention is 5.