I'm setting up a SharePoint page using SharePoint Online/Office 365.
For reporting purposes, I would like to ensure all entries in a particular column be exactly the same format, hence I would like to have validation in place for a text string in one of our fields.
I would like it to be YY-MM####-##. The YY being year, MM being month, #### and ##, values 0-9, and I want the hyphens to be required.
What formula would perform this?