About area charts
An area chart displays data values graphically as a set of points connected by lines. A different color designates each series. The area chart emphasizes change along the category axis. A stacked or percent stacked area chart also shows the relationship of parts to a whole.
An area chart that includes several series displays overlapping filled areas. A percent stacked area chart can show how percentages compare over time. For example, the area chart in Figure 19‑1 shows the percentage of order unit volume that each product group contributes to total order volume for a three‑month period.
Figure 19‑1 Area chart