This interactive stacked bar chart displays state-level data across two years. A dropdown menu selects the year, and the visualization animates the transition between the 2017 and 2018 views. The chart uses a categorical color scale to distinguish three data ranges. The code leverages D3 v5 APIs including `d3.csv`, `d3.scaleBand`, `d3.scaleLinear`, and `d3.stack`. Built with SVG elements, the bars and their total value labels are rendered directly, with a 750ms transition on year change.