help with date formula

[bsmoot1983]

I need the datedif of a cell from today to equal the number of months left on a project. The formula I have works except when it should say zero, it says #NUM!. 

[#2]

@bsmoot1983 

DATEDIF will return #NUM! if the end date of the project is earlier than today. You can get around this by wrapping DATEDIF in IFERROR:

=IFERROR(DATEDIF(TODAY(), end_date, "m"), 0)

Alternatively, use something like

=DATEDIF(TODAY(), MAX(end_date, TODAY()), "m")