Excel 2007 : How to create composite bar graph with pivot charts

Hey all,

I was wondering if anyone might be able to help me (or tell me if it's not possible) design a composite bar graph using pivot table/charts.

To summarize really quickly, I have a table with entries categorized by month and rating. So on the chart, I have the axis as the month, with the values being the count of the entries. What I'd like, if possible, is to overlay a color on that count graph that shows the quality. So in other words, if there are only two choices for quality: 1 and 2, and there were 10 entries for January, with 8 being quality of 2, the graph would look like this:

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|///1/// | /////////// 2 /////////// |
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Hopefully that makes sense....

Any guidance and help is greatly appreciated. Thanks!