Urban Development in United States 13 indicators covering urban development for United States. IndicatorLatest Year10-yr change Rank Population in the largest city 7.0% 2025 down 2.8% 148th Population density 36.81 people per sq. km of land area 2023 up 6.3% 166th PM2.5 air pollution, mean annual exposure 6.97 micrograms per cubic meter 2023 down 17.3% 176th Population in urban agglomerations of more than 1 million 160.79 million 2025 up 10.2% 3rd Population in urban agglomerations of more than 1 million, per capita 0.4704 units per person 2025 up 3.8% 15th Population in urban agglomerations of more than 1 million, annual 0.9145 % change on previous year 2025 down 23.6% 83rd Population in urban agglomerations of more than 1 million, per unit 0 units per US$ of GDP 2025 down 34.5% 104th Population in urban agglomerations of more than 1 million, per square 17.26 units per square kilometre 2023 up 10.8% 63rd Population in largest city 19.15 million 2025 up 2.7% 8th Africa's Development Dynamics (AfDD) Table 23 - Ecological 10,913 Hectares 2020 up 14.9% 3rd PM2.5 air pollution, population exposed to levels exceeding WHO 3.3% 2017 down 92.4% 186th Adjusted rural to urban parity index for achieving a minimum 0.8659 2018 down 14.6% 18th Transport equipment indicators — Available seat capacity for schedule 417.11 Per 1 000 inhabitants 2016 up 23.3% 33rd