LaVerne, if that formula is going into cell D2 then there is nothing at all in there that would cause a circ, and certainly no need to change your calc settings. Firefytr has given you a working answer based on your original ranges, and likewise there is nothing at all in there either that would cause a circ.
LaVerne, generally it's not needed to use circular references. It's very few and far between when they are actually needed. And even in those instances, I'd opt for another workaround. The generally accepted practice is to have a formula in a seperate cell, not referencing itself to perform calculations.