This function has no data in it on my new Scout. Is this because it is set to the variable service interval or has it just not been set up at the PDI?

If it's brand new, you probably haven't driven enough for it to calculate yet...

Its perfrectly normal Your car is on variable service and it takes several hunderd miles of driving before the computer can gauge when its likely to need servicing.

Thanks for that. It makes sense to me now.