A world map animates shifting population projections from 2020 through 2030, with circles sized by projected population using a square-root scale. Countries missing data appear in pink. The visualization uses d3.geoNaturalEarth1 for projection, d3.geoPath for country outlines, and d3.zoom for panning. Animated transitions update circle radii sequentially, while a size legend and color legend appear. Population data comes from a CSV file, merged with country geometries from TopoJSON via the topojson library.