I'm trying to use the below formula to calculate the amount of days between when a project is due, and when it was actually finished. Sometimes this will be earlier than the due date, sometimes after.
=NETWORKDAYS([Delivery Date]98, [Power Approval]98)
When the dates are the same, I'd expect the result of zero. But it returns one.
When the project is finished a day early, I'd expect a result of -1. But it returns -2.
When the project is finished a day late, I'd expect a result of 1. But it returns a 2.
What can I add to this formula to get this right? Or is there a better one out there to try?