Thanks guys, both suggestions were great.

The splitting of the file down to just that one sheet has improved it quite a bit but I am hesitant to have dates split up as I would then have to open numerous files, say by the month, if I wanted to add in some new parameter to assess. It currently calculates assorted "form selection methods" for the last 4000 contenders back to Jan 1 this year. If this was the case of breaking it up I would then have to open every month separated and input each new assessment criteria formula by column "copy and paste". This would make assessment slow and cumbersome when I have a new idea.

I think the Open Office way to go might be the thing, if it has an Access style database program. Will have a look.

The MrExcel website, looking like a copy of this website, may give rise to a few solutions, as well.

Many thanks for the help.