Excel 2007 : Filtered lookups for chart tables

This is likely a complex issue and follows my last post. I created a spreadseet that gives me weighted average prices for different materials purchased each month.

Using filtering in 2007, I can pick all the products and a month and get the figure.

What I can't do is pull that figure across to my charts. I have to manually filter and then copy/paste each value across. Can this be connected somehow?