This choropleth map shows global economic data using a color-coded scale, where a legend allows users to filter countries by economy type. Clicking a legend entry dims non-matching countries and highlights those with the selected value; clicking again removes the filter. The visualization loads world country boundaries from TopoJSON and economic classifications from TSV data, then uses `d3.geoPath` with the Natural Earth projection to render the map. The interactive components are built on `d3.scaleOrdinal` for colors and a custom SVG-based legend with click handlers.