Causes of urbanisation and counter-urbanisation in Zambia: Natural population increase or migration?

This article addresses the debate over the causes of urbanisation and counter-urbanisation in Zambia: Are urbanisation and counter-urbanisation caused mostly by net migration or are they caused mostly by the natural growth or decline of the urban population? Using population censuses, we apply the intercensal forward survival ratio method to measure net migration and the natural population growth of urban and rural areas in 1990, 2000 and 2010. The results show that the most important cause of urbanisation and counter-urbanisation was net migration rather than natural urban population growth or decline. Although natural urban population growth was roughly twice that of net migration, this had very little influence on urbanisation because it was matched by the natural growth of the rural population. We also address the causes of migration by examining employment trends. These results indicate that economic decline during the 1990s resulted in decreased urban employment and a dramatic rise in urban unemployment, which in turn caused migration from urban to rural areas. Conversely, during the 2000s, absolute employment grew and unemployment decreased, which corresponded with increased rural–urban migration (resulting in net urbanisation). Our findings also show that even during the period of net out-migration from urban areas and high urban unemployment levels, the resident urban-born workforce continued to grow strongly through natural increase. Thus, these results also show that urban population growth can increase substantially in the absence of urban economic growth, thereby increasing urban unemployment and urban–rural migration.