Robsibk – Was it for the 206 specifically? I have a few self-programmed CogG calculators for the 206, 206L, 341, 350, 355, 135 etc, plus a few extras like fuel, performance that sort of thing. They are an absolute doddle to do in excel. I can send you the 206L one if you want it, (if I can find it!)just to see how it works.
Ps – They also work in a Psion 5