Formula similar to WORKDAY but working backward from a due date

[Branden]

I receive a due date and have to calculate backward to identify different milestones in our projects. What formula(s) do I need to use to make this work? I've attached a picture of what I'm trying to do. 

Thanks in advance for the help!

[Sistema_Aotearo]

You're gonna need to make a field for each of these milestones. Then subtract the days based on the final date, "Completion", which I assume is the due date.

An example would be to make a formula field, "Production Fee Due" with this formula:

DATEADD({Completion}, -1, 'days')

The "Start Date" field would have:

DATEADD({Completion}, -42, 'days')

If your due date is in the middle, you can add days on future dates by removing the "-" in front of the number.

Additionally, if you want the number of days to be variable, you'll have to create a number field for each milestone. Your formula would look like this instead:

DATEADD({Completion}, -{Production Fee Days}, 'days')

Let me know if this is what you're looking for 🙂