> A denominator can never be 0.
Well, yes. As my degree is in mathematics, I realized that.
> no fields on forms should accept the value 0 if they will be used as the denominator of a division calculation
I would assert that a better way to handle it would be if the value in I4b1a was zero (it is), then fields b,c,d should be disabled and a calculated zero put in box I4b1d. That would eliminate having to put in faux data just to satisfy the error checking.
