Quote Originally Posted by Darlo
Excellent thanks, this works.

I think I'm getting to grips more with sumproduct formulas now. Does the * within a formula split up the criteria? And also what does the two -- mean at the start of the formula? is this saying that there are multiple criteria within the formula?
see the link below for explanation

http://www.mcgimpsey.com/excel/formulae/doubleneg.html