Boundaries & population of cities: USA (1850–2020) and World (1975–2025)

This repository contains: 1) City boundaries and population for the United States (1850-2020) and the world (1975-2025). Data are organized around the idea of cluster_growth: a stable city boundary computed for a time window (y_1, y_2), within which growth is measured consistently. Among the numerous city definition, this definition has two main advantages: (i) it dynamically adjusts as urban areas expand; and (ii) it is consistent across space and time, facilitating robust comparative analyses. 2) Data and projections of the share of world population living in cities of 1 million people or more between 1975 and 2100. For more information see the paper and the code.