Hello again Trowa,
Thanks for that. Much appreciated.
This is actually another of the wife's projects so you've saved me from the dog house again!
After posting the thread, I played around with formulas (formulae?) for about an hour and found that the following ISBLANK function works well also:-
but I like your formula better so I've inserted it to replace the ISBLANK one.
I can't believe how lazy the wife and I have become (can't even type in a date a few columns away)!!
BTW, thanks for explaining the formula also.
Anyway, grazie molto.