Validation Rule Error

[London]

Thank you everyone for taking a look and trying to help me solve this problem. But I think the solution is not to use Access to do these calculations at all. I've been learning more about Excel, and specifically PowerPivot, and I think the best thing is to do the calculations in an Excel spreadsheet and then import the results into Access for storage. The only downside is I don't think Excel or PowerPivot has the capability to create forms for inputting data, but that's a small sacrifice to make for a more workable solution.

[Mickjav]

A Lot of those calcs can be done at the report stage.

The tables I have put together would do the job with the additions I was going to add.

I did make one mistake in the image I related the Classes to Clients when it should have been to Client Sites.

It may look compicated but it will work a lot better then excel but if thats what you want I wont waist anymore time on it.

good luck

mick

[London]

Your grasp of Access is much more comprehensive than mine, I think I understand the logic looking at how you have the tables laid out, but I'm definitely still a little lost. My preference would definitely be to use Access over Excel, but my general lack of knowledge of Access made it seem impossible to do that. If you are able to get it to work in Access, I would be very appreciative. I've been playing around with Excel and it definitely is not as powerful as Access. Also because the table is so large, not having the ability to create a form to input the specific data that I need will make it challenging to train anyone else to do the data entry. Thanks again.

EDIT: Apparently, you can actually create forms for inputting data in Excel. So I'm going to keep playing with that tonight and tomorrow and see whether or not it will work for what I want, then report back here.