An interactive bar chart displays median home prices for New York State counties across 2022–2024, sorted by price for the selected year. A React frontend manages state for year selection, tooltip visibility, and county highlighting, while D3 v7 handles SVG rendering, scales, axes, and animated transitions. Hovering a bar reveals a tooltip containing a mini sparkline of that county’s three-year price trend, drawn with `scalePoint` and a D3 line generator.