Stacked area chart
In a stacked area chart, multiple series are stacked vertically, as shown in Figure 8-7. The example shows that the stacked area chart is suitable for the data because the chart displays totals for all series as well as the proportion that each series contributes to the total.
The height of the top line shows the total value for each quarter. Each shaded area represents the sales amount for a specific region.
Figure 8-7  

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