Dave,

Thankyou for the continued thought, the second reply and thankyou for sharing your knowledge.

Now I have a working example I will be exploring the full range of possibilities that this formula and the previous one will bring.

I enjoy learning new things and I to enjoy sharing what I have learnt, mind you it is a very much lower level than yourself, but it is good to know that you can make someones day a little brighter by a simple formula.

Thanks once again

Paul...