What are area graphs primarily used for?

Area graphs are specifically designed to illustrate how cumulative values change over time. They effectively show trends and the progression of data over a series of intervals, such as months or years, by filling the area under the plotted line. This fills a visual space that represents the total levels of a particular quantity, allowing viewers to easily grasp how these values evolve.

The use of area graphs is particularly beneficial in scenarios where it's important to see both the overall total and the individual components contributing to that total, as the different segments can often be stacked. This layered approach helps to highlight the overall trends as well as the individual contributions to that trend, providing a clearer understanding of cumulative growth or decline.

In contrast, other options like displaying static data or presenting product comparisons do not capture the dynamic nature of cumulative change over time. Visualizing customer demographics might utilize a different format better suited for comparative statistics rather than cumulative trends. Therefore, area graphs excel in scenarios where monitoring changes in cumulative values is crucial.