I want to be able to define the number of cells in a column that will be included in a calculation.

=SUM(A5:A25)/2

So in the above example I have selected 20 cell in column A. I want to be able to set the number via a slider on the spread sheet to capture any number of cell below the cell with the formula in it. So, and I know this does not work but, =SUM(A5:A(X))/2 where X equals the number of cells that I want included. I want to avoid VBA because this will update a graph and I don't want to run a macro every time the data gets changed to update my graph.

I have gone through the Excel 2003 Bible, called MS Office support and combed the web. There must be a simple way to accomplish this without a macro.

Thanks to all. Michael



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