I would have thought that with their profits, Tesco could buy a solution!
I am not clear which cell is the LFL target and actual, but you should just
add a test to cater for the actual being blank as well. Also, I don't know
why your formulae are fully absolute, as this does not make it easy to
extend for more stores.
So, it would be something like
=AND($C12<>"",$C12<$C75)
but adjust to what you actually know about those cells

Signature
HTH
Bob Phillips
(remove nothere from email address if mailing direct)
> basically im very new to excell and im trying to create a sales sheet
> for my company (tesco) on store performance
[quoted text clipped - 15 lines]
>
> can anyone help me pls