The default for viewing the free/busy section of the calendar is set for two months by Microsoft (current month plus one month). To make the free/busy section viewable for longer:

1. Log into Outlook; you can be on the email inbox to make this change.
2. Click Tools.
3. Click Options.
4. Click Calendar Options.
5. Click Free/Busy Options, and make your change. 12 months is usually a good number.

Note: You can’t do this for your manager from your computer; this can only be changed on the computer that the owner of the calendar uses.