This chart displays the population distribution across six U.S. states, broken down by seven age brackets. Each state’s data is shown as a group of colored bars, with a legend that allows users to click on age categories to filter which bars remain visible. The visualization uses D3 v5 with a band scale for grouping, a linear scale for the y-axis, and an ordinal scale for colors. It is rendered as an SVG, and clicking a legend item triggers a transition that updates the visible bars and rescales the axes.