I meant: can you put in words what the calculation needs to be? Before you can start thinking about formulas, you should have an idea of what you want to do. Do you need to look up data or compare data? Sum, average, whatever? If you sepecify the logic, someone here can give you the formula and/structure translated into Excel. But you need to be able to describe the steps that lead to the result. If not in Excel terms, then in plain words.