SB
There are several sites that will show you techniques for using clustered
and stacked bar charts.
http://peltiertech.com/Excel/Charts/index.html
http://www.andypope.info/charts.htm
http://www.stfx.ca/people/bliengme/ExcelTips.htm
From a data visualization standpoint, stacked and clustered bar charts are
not the best choice. Cleveland's chart interpretation research has shown
that chart readers can interprete position along identical, non aligned
scales better than length.
This page gives a brief introduction to data visualization with Excel and
the does and don'ts of Excel charting. Just because Excel has a
clustered/stacked chart capability doesn't mean that you should use it.
http://processtrends.com/TOC_data_visualization.htm
As an alternative to stacked/clustered bar charts, I suggest panel charts,
comparable to Tufte's small multiples or Cleveland's trellis charts.
http://processtrends.com/toc_panel_charts.htm
If you'd like to try panel charts, let me know and I will be glad to walk
you through the process.
Here's my anti-spam e-mail address. Remove the extra characters if you would
like to contact me.
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