HELP WITHINTEREST/FOREX RATE ANALYSIS

Well, first of all, you can't set up a database in Microsoft Excel. It's a spreadsheet application but I think what you mean is you want to set up a spreadsheet that would calculate a rate of interest based on some kind of past history.
You would have to set up the sheet with the trend/history information and then use a formula in the column that you want to stand for the current rate. There are numerous ways you can do that and how you would do it would depend upon what your past information was. If you can make an equation out of your information, you can do it in Excel.
I recommend you going to TOOLS and using the ADDINS function to add in the Analysis Toolpack which has extended financial functions that may have what youare looking for, and add-in the Solver. Either way you are bound to hit what you are looking for.
Good luck! Debbie