I have a number field that is optional to be updated. Zero is a legitimate value to enter into the field. However, if the field is left empty, it still returns zero. So a test for zero doesn't tell me if that was the original value or the updated value. I'd like the field to return blank if the field wasn't updated by the user to zero. 

I tried the following script that i found elsewhere, however it doesn't seem to work in o365.