This is bugging me so if anyone can help I'd be very grateful. If I have a
range of numbers, say A1:D1 and I have a very simple formula to sum those
numbers is it possible to force the result to represent say "#N/A" if one of
the numbers in my range A1:D1 is missing. In other words, unless I have a
figures in each of the cells A1:D1 I don't want the calculation to happen.

Many thanks as always
--
Andy T