David Bloom (),
Tarun Khanna and
Patrick Salyer Additional contact information David Bloom: Harvard School of Public Health
Tarun Khanna: Harvard Business School
Patrick Salyer: Harvard School of Public Health
This paper examines data on urbanization. We review the most commonly used data sources and highlight the difficulties inherent in defining and measuring the size of urban versus rural populations. We show that differences in the measurement of urban populations across countries and over time are significant and discuss the methods used for these measurements, as well as for projecting urbanization. We also analyze recent trends and patterns in urbanization. Finally, we describe the principal channels of urbanization and examine their relative contributions to the global urbanization process.