This interactive dashboard synchronizes a bar chart and a pie chart to explore categorical frequency distributions across multiple states. Hovering over a bar updates the pie chart and legend to show the breakdown of the selected state’s data into low, mid, and high segments, while moving the mouse away restores the overall totals. Built with React and D3.js v3, the visualization uses SVG for rendering and animated transitions to smoothly update the bar heights, colors, and labels, as well as the pie chart slices. The bar chart uses an ordinal scale for the x-axis, and the pie chart’s updates are driven by calling its `update` function with new data.