We had been using the native Project field "Progress Status". An issue we found with this is it takes into account the time portion of the planned completion and actual completion. We don't worry about the exact time of delivery, we always aim for due by end of day. This field would say a job was late even if it was minutes past that planned completion time. So I went searching for ideas and found your post. I'd say, if you do pay attention to the time stamp, then you might be able to get away with using that native field (or not since you're using the custom field you descried above). For us, I took your formula but added "CLEARTIME(date)" to get the time portion out of the calculation. It looks like this in full: IF(CLEARTIME(Actual Completion Date)>CLEARTIME(Planned Completion Date), "Late", "On Time") We were starting to worry that our on time delivery dropped from 98% or better before launching WF down to 75%. This custom formula showed that we're doing ok, and that we can keep using WF ;) , with a 95% on time delivery since launching. I hope my added comments are helpful to the community! David Bray Trane US Inc