This visualization is like a line graph, but with a colored area below the line. Use an area graph when you have multiple metrics and want to visualize the area expressed by the intersection of two or more metrics.
This visualization is like an Area Chart, but each series begins at the top of the previous series.
A new visualization setting on area stacked visualizations turns the chart into a “100% stacked” visualization.
Here is a video on “100% stacked visualizations”: