Brilliant thanks, I will definitely take a look at the tutorial when the little one has gone to bed. It will definitely make life easier if I understand it.

And many thanks for providing a formula.

I pasted this into D4 (Where I want the results for what has been ordered) and I expected the answer to be 5 shifts for Derby OT Project Funded in week 1, however, it returns 2.

Could I be doing some wrong?

I will take a proper look at check the obvious later tonight!