[andyjohnson0]

I concur on its authenticity. It looks like someone's craft project using an old calendar.

Nicely done, though, however it originated: I wish I could letter and doodle so neatly.

[Spooky23]

I started working in offices around 1998 as an intern. The place I worked used email heavily, but had no shared calendar. Definitely people who did stuff like this. My boss had a bound dated diary book that he used to record what happened (vs where he had to be) decorated which he decorated with interesting doodles, etc.

We lost something with Outlook for everything.