Outlook seems to generate multiple copies of my calendar. I have the following listed for My Calendar
Calendar
Calendar in Archive Folder (7)
Calendar (2) in Archive Folder
Calendar (3) in Archive Folder
Calendar (4) in Archive Folder
Calendar (backup) in Archive Folder
Calendar in Archive Folder
Calendar (backup) in Archive Folder

How do I get information on managing them?

Where they created when I archived Outlook?

Why are they generated and can I just get rid all but my current one?