This interactive visualization combines a map of U.S. states with a time-based histogram of air quality index (AQI) values. The map shows data points as blue circles, with radius scaled by AQI using a square-root transform. A separate histogram displays the monthly average AQI over time, binned by month. The visualization uses React with D3 v5 APIs, including `d3.geoAlbersUsa` and `d3.geoPath` for map projection and rendering, and `d3.histogram` with `timeMonths` for binning. Data is loaded from a CSV file containing ozone samples with geographic coordinates and dates.