The Disparate Roles of Migration, Reclassification and Vital Rates in the Urban Transition in Sub-Saharan Africa

Philippe Bocquier, UCLouvain
Ashira Menashe Oren, Université Catholique de Louvain
Stefanija Veljanoska, Université Catholique de Louvain
Joan Damiens, University of Helsinki

Rural to urban migration is often considered the driving force behind urbanisation, yet shifts in proportions urban can also result from reclassification and changing vital rates. We aim to identify the contribution of these demographic forces to urbanisation and examine these trends in sub-Saharan Africa. Using 39 IPUMS censuses and 80 DHS surveys we directly estimate rural-urban migration flows between 1976 to 2016. We compare these estimates to net rural-urban flows based on UN data to ascertain the contribution of reclassification to urbanisation. We also examine migration trends between rural-capital city, rural-other urban, and other urban-capital city flows for a nuanced understanding of the urbanisation process. Our models indicate that natural growth is negligible at the beginning of the urban transition, and then becomes dominant once the percent urban exceeds 30%. In contrast, the contribution of rural-urban migration declines, and we find instead greater urban-capital city migration flows.