Dear All: I made a mess of the post under Array and Do Loop. Let me start over again and post my question in a simple way. The basic issue is of looping:

Here is an example:

A B C 5000 6000 7000 10000 4000 9000 7000 12000 I want to construct a variable Z. If B > A then the formula is Z = C-B/A But if B < A then the formula to be applied is Z = (C-B/A)+.5((A-B)/A) Thus the output should be: A B C Z 5000 6000 7000 0.2 5000 4000 9000 1.1 5000 7000 12000 1.0 10000 6000 7000 0.3 10000 4000 9000 0.8 10000 7000 12000 0.65

The problem I am having is looping the program back to iterate over all the values of A for all the values of B (and C).