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"...multivariate comparisons provide for more meaningful analysis than do single variable distributions ..
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".. pie charts should be rarely used, if at all"
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"3D pie charts are even worse"
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"Forcing the reader to draw comparisons across two pie charts is also a bad idea"
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"All the information in ..pie charts ... can be conveyed more precisely ... in a simple bar chart."
Excel provides both pie and doughnut charts. Data visualization problems associated with pie charts also apply to doughnut charts.
Excel users have alternatives to pie/ doughnut charts. Dot plots can be much more effective. Panel dot plots like the chart on the right can be used to show changes over time with small multiple - trellis like displays using Excel charting, data transformations and dummy axis techniques explained in this site.
The panel dot plot chart (above - right) shows the distribution of proved world oil reserves by region for 1984, 1994 and 2004 from data in the BP Statistical Review of World Energy - 2005.
The initial version of this chart was prepared using 3 doughnut charts, one for each year. (click thumbnail to see BP's original chart).
This workbook download shows you how to make panel dot plot charts in Excel.
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