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One big issue with Excel © is the intrinsic mixture of data and of programs (formulas). VBA can help a bit here, but if you really want to separate the data from the programs you need to use a database.
My friend and former colleague Mike Robinson developed a tiny but powerful simple database. It consists of two tables and two stored procedures. I use this with MS SQL Server ©.
You can feed data into it via Excel and retrieve data with Excel.
If you are interested in downloading the 46 KB database documentation (pdf file) go to my Download page, please.