Stacked Column Charts display the comparison of the quantitative value each part of the category brings to the whole category. Each of the stack components shows its relative contribution to the entire bar and the entity as a whole.
In this Stacked Column chart, a revenue volume (in dollars) shown from selling several products in several states. Each legend item represents a series (a state). By clicking and hovering legend items the corresponding series can be shown and hidden, making the Y scale to recalculate itself. Each stacked column represents one of the products.