Percent stacked area chart
In a percent stacked area chart, multiple series are stacked vertically, and the values appear as a percentage of the whole. As Figure 8-9 shows, the sales values are displayed in percentages, instead of the actual numbers, as shown in the previous area charts.
Figure 8-9  
The percent stacked area chart is meaningful only when displaying and comparing multiple series. If displaying only one series, the percent stacked area chart looks like the example in Figure 8-10. The sales percentage of one region, compared to the whole, is 100%.
Figure 8-10  

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