A heatmap displays annual property-crime rates for U.S. states from 2000 to 2019, using color intensity to show per-100,000-person offense counts. It uses `d3.scaleThreshold` with `d3.interpolateBlues` to map rates to colors and a sequential color scale for fill, while `d3.legendColor` provides a threshold legend. Data comes from the CORGIS smoking dataset, filtered for property crimes. Tooltips reveal exact values on hover, and axes are labeled using `d3.axisBottom` and `d3.axisLeft`, with the SVG rendered via D3 v6.