Help with this file - keep getting "Invalid" error...

Hi,
I’m having trouble with this file:

It’s for a stock trading class, and it’s suppose to be a template.

When I try to put a value in the “Distal” box on any of the tabs, it comes back with an “Invalid Value” error.
I’ve been told that it works in Excel, so I’m thinking it’s some kind of compatibility issue.
I’m not sure how to edit what’s going on behind the scenes, or how to check it for compatibility.

Any help would be appreciated. I’ve tried in Open Office, Google Docs, Numbers, and Libre. Same issue every time.

Thanks

Ron