This visualization shows how the 435 seats in the US House of Representatives were reapportioned between the 2010 and 2020 censuses. Concentric rings around each state centroid represent the number of congressional seats, with the arc radius scaling inversely to population per seat using d3.scaleSqrt. The map uses d3.geoAlbersUsa and d3.geoPath to render state polygons, while seat counts and population data come from a combined CSV loaded with d3.csv. States maintain their existing seats between censuses, and newly added or lost seats are represented through the ring structure.