It is widely believed that urbanisation is occurring faster in sub-Saharan Africa than anywhere else in the world, as migrants move from rural to urban settlements. This is a fallacy. While the populations of numerous urban areas are growing rapidly, the urbanisation levels of many countries are increasing slowly – if at all. Natural increase, rather than net in-migration, is the predominant growth factor in most urban populations. African governments, policymakers and international donors need to acknowledge fundamental changes in urbanisation trends, and respond to the irrefutable messages these impart about urban employment, incomes and economic development.

By Deborah Potts is Reader in Human Geography at King’s College, London. She is the author of “Circular Migration in Zimbabwe and Contemporary Sub-Saharan Africa” (James Curry, 2010).

In November 2010, a perusal of UN-Habitat’s “Urban Indicators” database revealed some curious statistics. The proportion of Kenyans living in urban settlements had seemingly reduced from 34% of the total population in 2001 to 22% in 2010. Was it really possible that such a huge number of people had left Kenyan towns for rural areas in the first decade of the 21st century? After all, it is common knowledge that Kenya is urbanising rapidly.

The UN-Habitat data indicated a reduction in the urbanisation level of 11 other mainland countries in sub-Saharan Africa between 2001 and 2010 – Tanzania, Uganda, Benin, the Central African Republic, the Republic of Congo, Equatorial Guinea, Guinea-Bissau, Lesotho, Mauritania, Niger and Senegal. The declines in Tanzania (from 33% to 26%), Mauritania (59% to 41%), and Senegal (48% to 43%) were as startling as that in Kenya.

Neither the UN-Habitat data nor “common knowledge” accurately represents what has been happening to migration patterns and urban economies in sub-Saharan Africa. The process of urbanisation – whereby an increasing proportion of the population lives in urban settlements – is occurring far more slowly in Africa than is usually reported. This has crucial economic and developmental implications which cannot be ignored.

Rapid urban population growth is evident throughout sub-Saharan Africa. However, a burgeoning urban population does not automatically denote a rise in a country’s urbanisation level. Even if a national population grows at 3.5% a year, doubling in 20 years, urbanisation – in the sense used in this Counterpoint – will only occur if the rate of urban population growth has exceeded the rate of national population growth.

Definitions of “urban” vary from country to country. When settlements of a few thousand inhabitants are defined as urban, as is the case in Cameroon, the urbanisation level of a country will be higher than if the commonly-used threshold of 20,000 inhabitants is applied. If African countries adopted the criteria used in India, their populations would be classified as much more rural. Confusion at census time over urban classifications can significantly inflate the apparent level of urbanisation.

In time, fictitious figures became facts by being constantly re-stated

UN-Habitat and the World Bank are the most frequently cited sources of urban population statistics. However, their data are often misleading, and have exaggerated urbanisation levels. Most African countries experienced very rapid urbanisation in the 1950s, 1960s and 1970s. Thereafter, the conduct of censuses became erratic, and the timely publication of census data less common. Yet population projections made by UN-Habitat and the World Bank assumed that the rate of urbanisation was continuing unabated.

Politicians, civil servants, donors, urban planners, city authorities and academics persisted in using urban population data based on increasingly flawed assumptions about growth rates. In time, fictitious figures became facts by being constantly re-stated. Even when census data became available which provided a corrective, it could be many years before datasets and projections were amended accordingly.Politicians, civil servants, donors, urban planners, city authorities and academics persisted in using urban population data based on increasingly flawed assumptions about growth rates. In time, fictitious figures became facts by being constantly re-stated. Even when census data became available which provided a corrective, it could be many years before datasets and projections were amended accordingly.

In the late 1990s and 2000s, many new censuses were published in sub-Saharan Africa. These revealed significant divergence in the pace of urbanisation. Many countries are urbanising very slowly. Some have de-urbanised. Very few have been experiencing rapid urbanisation.

Despite the availability of more extensive and reliable data, there are still important gaps. In Nigeria, the country with substantially the largest population in sub-Saharan Africa, every census since 1952 has been highly contested – and there is still no official breakdown of urban populations. The Democratic Republic of Congo, said to have the third largest population in sub-Saharan Africa, has not conducted a census since 1984. This renders often cited population figures – and projections – for Kinshasa, the capital city, little more than guesswork. Although it is frequently asserted that Luanda’s population growth has been extremely rapid, the size and dynamics of Angola’s towns and cities are equally uncertain.

Reports published by UN-Habitat, including the series The State of African Cities, usually acknowledge that urbanisation is slowing. However, the implications tend to be ignored in subsequent analyses which seem to presume that urbanisation remains rapid. While the recent radical revisions of urbanisation levels in UN-Habitat datasets suggest that past errors are being recognised, the issue was not discussed in The State of African Cities 2010.

My attention was first drawn to a discrepancy between common knowledge about African urbanisation and empirical evidence when analysing Zambia’s 1990 census. This clearly showed that the population of the Copperbelt towns was dwindling in size relative to the national population, and that urban-rural migration exceeded rural-urban migration. At the time, recognition of these significant trends – and their implications – appeared to be confined to Zambia’s national census reports.

Subsequent analysis of other censuses and demographic surveys confirmed that received wisdom about urbanisation required reassessment. The picture across sub-Saharan Africa was very mixed, as was to be expected for a region with so many countries, and such varied geography and history. But evidence of slowing urbanisation, and radical changes in migration flows, was corroborated by academics working in West Africa.1

Figure 1 shows four countries where the urbanisation level declined – Zambia, Côte d’Ivoire, Mali and the Central African Republic (CAR). In the ten countries in Figure 2, the urbanisation level was stagnant or increased very slowly. The four countries in Figure 3 – Burkina Faso, Cameroon, Tanzania and Kenya – experienced increases in urbanisation levels at a rate more in keeping with common knowledge about the rapid pace of African urbanisation. Drought and conflict played important roles in some of the 18 countries – but economic factors were the predominant influence.

When interpreting the graphs, the key detail to consider for each country is the difference between the national population growth rate (the blue bar) and the growth rates of individual cities or groups of towns (the green bars). Where the bar for a city or group of towns is shorter than the national population bar, the city or towns were losing population share, or counter-urbanising. If all urban areas were losing population share, the country was ruralising. A bar for all urban settlements is not included for every country, due to variable definitions of “urban” and gaps in the data. Where this is the case, a reasonable alternative is shown.

Population growth in a capital city and/or other large town that exceeds the growth in the national population does not automatically imply a significant increase in the national urbanisation level. Rapid population growth in a capital can be counteracted by slower growth in other towns. In Malawi, in Figure 2, Lilongwe’s population grew by 4.3% annually between 1998 and 2009. But this was offset by average annual population growth of 3.1% in all other Malawian towns, restricting the increase in Malawi’s urbanisation level to a mere 1% in a decade – from 14% to 15% of the total population. UN-Habitat records a 5% increase from 15% to 20% for the same period.

In Uganda, also in Figure 2, the 3.7% annual population growth of Kampala looks impressive until it is compared with the 3.4% annual growth rate of a predominantly rural national population. Uganda’s urbanisation level, like that of Malawi, increased by just 1% in the inter-censal period – from 11% to 12% of the total population. An influx of refugees displaced by conflict explains the extremely rapid growth of Gulu and Lira, in northern Uganda. In Niger, the increase in population share of the 38 main towns also rose by just 1%, from 15% to 16% of the population. Although the capital, Niamey, attracted many migrants between 1988 and 2001, some large towns experienced net out-migration.

In countries in Figure 2 where the capital city did not increase its share of the total population by much, if at all, the national urbanisation level often rose by less than 1%. The urbanisation level in Benin, which uses an urban threshold of 10,000 inhabitants, increased by less than 1% between 1992 and 2002, to 38.8% of the population. In Togo, the urbanisation level in 2010 had risen a mere 0.8% above its level thirty years earlier.

The countries in Figure 3 experienced significantly higher net in-migration to more large and medium-sized towns than occurred in the countries in Figure 2. In Burkina Faso, the urban share of the population rose from 18% to 22% in a decade. In Cameroon, towns with 10,000 inhabitants or more increased their share of the total population from 33% to 44% in just under 20 years. In Tanzania and Kenya, urbanisation was more uneven.

The population of Tanzania’s largest city, Dar es Salaam, increased at a rate well in excess of the growth in the national population during the 1990s. The growth of Arusha was even faster. But the rest of Tanzania’s dozen principal urban centres, taken together, did not increase their overall share of the population. Five of them were counter-urbanising. Kenya’s major towns also experienced very variable growth. The country’s inclusion in Figure 3 is largely attributable to Nairobi, whose population grew by 9% annually in the 1960s and continued to expand by about 5% annually from the 1970s to the 1990s.

Tanzania’s 2012 census will merit close scrutiny. In 2002, 20% of Tanzania’s population lived in towns with more than 10,000 inhabitants. But it was difficult to quantify how much this had increased since the 1988 census, due to complex definitional issues. Nairobi’s growth fell to 3.9% a year in the most recent inter-censal period, which compares to 3% annual growth in Kenya’s national population. Preliminary analysis, as yet unverified, suggests that eight of eleven main established towns recorded in previous censuses grew more slowly than Kenya’s national population between 1999 and 2009.

In 2008, publication of the Africapolis dataset for the 16 countries of West Africa provided further evidence of slow urbanisation.2 The project used satellite evidence to compare census and other data with what could be deduced from the built-up areas observable on the ground. The team which analysed the data found that the urbanisation level in West Africa was about 34% in 2010, and might reasonably be expected to increase to 35% in 2020. The painstaking Africapolis study demonstrates that UN-Habitat’s The State of African Cities 2008 seriously over-estimated urbanisation levels across the region when predicting that more than half of the population of West Africa would be urban-dwelling just before 2020.

Census and other demographic data do not corroborate the received wisdom about rapid urbanisation in sub-Saharan Africa. The evidence in many countries indicates an increase in the urbanisation level of only about 1% per decade

The Africapolis evidence for Nigeria is equally arresting. The UN Department of Economic and Social Affairs declared that Nigeria’s urbanisation level in 2006 was 49%.3 The Africapolis team estimated 30%. The UN figure implies an urban population of 69 million, while that of Africapolis implies an urban population of 42 million. Triangulation between the Africapolis datasets and what can be discerned from the 2006 census suggests that if the reported national population growth rate of 3.2% was correct, the population share of about four out of five of Nigeria’s major towns was stagnating or in decline.4

African censuses are not always easy to interpret. Some are too problematic – or contested – to use. But there has been a marked improvement in recent years, and the data are certainly a better resource for analysis than fanciful projections. Census and other demographic data do not corroborate the received wisdom about rapid urbanisation in sub-Saharan Africa. The evidence in many countries indicates an increase in the urbanisation level of only about 1% per decade.

The primary cause of much slower urbanisation since the 1980s was economic. In the 1970s, after the first oil crisis, many non-oil producing countries in sub-Saharan Africa borrowed substantial sums at attractive, but floating, rates. When oil prices – and inflation – soared again in 1979, the costs of servicing the debts became unsustainable. Governments were forced to refinance with conditional loans from international financial institutions, principally the International Monetary Fund and the World Bank, which in turn demanded economic reforms. Trade was liberalised, and public sector expenditure was cut, as structural adjustment programmes were adopted to balance national budgets and improve macroeconomic stability.

The economic consequences of structural adjustment programmes varied from country to country depending on terms of trade for exports, governance, geographical location, and experience of conflict. But the impact on urban livelihoods was dire throughout sub-Saharan Africa. Real urban incomes, which in many countries had already fallen because of the oil crises, plummeted as currencies devalued and wages were reduced. Urban populations bore the brunt of formal job losses. The situation in towns was worsened by the removal or lowering of various public subsidies – particularly for staple food, but also for housing and schooling – which had bolstered urban living standards.

In Nigeria, real minimum wages fell by 90% between 1981 and 1990

The extent to which incomes were ravaged by structural adjustment cannot be overstated. In Zambia, real minimum wages fell by 35% between 1970 and 1985 – before the effects of structural adjustment really began to bite; in Tanzania, they fell by 82% between 1972 and 1989; in Abidjan, Côte d’Ivoire, by 81% between 1978 and 1988; in Nigeria, by 90% between 1981 and 1990; in Ghana, by almost 90% between 1974 and the end of the 1980s. In Uganda, a decline of 90% between 1972 and 1990 would have been worse had it not been for some recovery in the decade after President Idi Amin was ousted in 1979.5

While real minimum wages have improved in many countries since the end of the 1990s, they remain well below their value in the early post-colonial period. Furthermore, minimum wages in the formal employment sector – even if enforced – no longer tell us much about the income of most urban families. The earnings of those who have retained formal jobs have been so eroded that in many households everyone must work if the family is to survive. Urban labour markets have substantially informalised in most of sub-Saharan Africa. While Africa’s informal economies are a testament to the resilience and ingenuity of millions, the income generated by individuals is typically very low.

There is no shortage of research showing that poverty levels in sub-Saharan Africa are still worse in rural areas than in towns and cities. However, when higher living costs in towns are factored in, the gap between rural and urban living standards narrows sharply and – in some cases – reverses for the lower-income urban groups. Hardships being experienced in Europe and America since 2008 pale by comparison with the consequences of structural adjustment in urban Africa.

Economic liberalisation and attendant crises rendered sub-Saharan Africa unable to compete. Global competition was forced upon towns and cities before most governments had moved beyond the earliest stages of establishing an industrial and manufacturing base. By comparison with Asian competitors, most African cities had inadequate human capital with which to entice substantial investment in a competitive, globalised economy – especially those needing large, skilled or educated workforces. Chronic under-investment in infrastructure has proved a further disincentive.

If countries in sub-Saharan Africa are to stimulate and sustain rapid – and economically favourable – urbanisation, they will require massive investment in industries which collectively employ hundreds of thousands of low-skilled people, rather than enterprises employing hundreds. This is the type of investment which Asian cities have succeeded in attracting. While much of urban Africa was de-industrialising in the final decades of the twentieth century, Asian cities created millions of jobs. As a result, cheaper goods from China and other foreign competitors caused the closure or downsizing of huge swathes of Africa’s formal urban-based industry.

GDP growth rates have improved in many African countries since 2002. However, this positive development has not proved a catalyst for job creation and urbanisation. Growth has been attended by greater inequality in the distribution of resources. In some countries, an apparent improvement in urban poverty rates has occurred simply because further decline would have been almost impossible.

Net in-migration – a positive balance between migrants moving into and out of towns – is a crucial element of urbanisation. In countries with predominantly rural populations net in-migration must be substantial if rapid urbanisation is to occur. In the common portrayal of urbanisation in Africa, cities are often described as being “swamped” by migrants.

Academics and urban planners puzzle over the seemingly irrational behaviour of Africans moving to urban areas with few formal job opportunities. In reality, in many countries the proportion of migrants to towns and cities who leave again – a phenomenon known as circular migration – has increased significantly. The flow of rural-urban migrants is substantially countered by that of urban-rural migrants, and the average length of time spent in towns has decreased. The impact of more, and faster, circular migration is to reduce net in-migration, thereby slowing urbanisation. Confronted by economic insecurity and other hardships worse than where they came from, people behave as rationally in Africa as anywhere else.

Confronted by economic insecurity and other hardships worse than where they came from, people behave as rationally in Africa as anywhere else

Circular migration trends can be traced in some African censuses and have been detected by many social science surveys. In the 1990s, research undertaken in Harare, Zimbabwe, revealed an increasing number of migrants planning or expecting to leave the city.6 At the same time, net out-migration – counter-urbanisation – was occurring in neighbouring Zambia. In some regions, out-migrants from rural areas no longer even aspire to move to towns in their own countries. Large-scale migration research undertaken in francophone West Africa has demonstrated that many rural out-migrants seek to move straight to overseas destinations, mainly in Europe.

Urban populations are still growing in sub-Saharan Africa, in many cases rapidly. But growth is largely attributable to natural increase as births exceed deaths in towns, especially among the poorest sections of the population. The large-scale, permanent or semi-permanent rural in-migration required to generate sustained increases in urbanisation levels has evaporated since the 1980s.

Migration is volatile, and highly sensitive to economic signals. Migration patterns which have developed since the 1980s in sub-Saharan Africa – particularly in non-oil exporting countries – will change. If urban economies weaken further, net in-migration may fall further and countries will experience even slower urbanisation, or counter-urbanisation. Conversely, improved economic performance which is accompanied by the creation of very large numbers of reasonably paid urban jobs and substantial investment in infrastructure could stimulate in-migration, reduce the speed and frequency of circular migration, and boost urbanisation.

The urban scenario can alter quite rapidly. Zambia’s 2010 census demonstrated that the country has begun to re-urbanise, most probably because of changes brought about by the huge increase in the price of copper since 2003. Despite recent trends, Zambia has still not regained its urbanisation level of 1980.

This Counterpoint does not seek to suggest that urbanisation levels have peaked in sub-Saharan Africa, nor that the future is necessarily rural. But it does need to be recognised that it is simply not true that the region urbanised rapidly in the 1980s, 1990s and 2000s. There is too much evidence of countries experiencing a very slow shift from rural to urban, amounting to about 1% per decade, and of variation between countries, for this generalisation to be allowed to persist.

Misleading projections based on inaccurate datasets obscure important policy messages about urban economies, urban poverty and migration trends. For much of sub-Saharan Africa, the foreseeable future will remain predominantly rural. Predictions of a majority of Africans living in towns by 2020 or 2030 are not supported by evidence. The demands placed on policymakers by rapid urban population growth driven by natural increase are quite different from those created by net in-migration. However, they are no less complex – or substantial.

1 See, for example, Beauchemin, C., and Bocquier, P., Migration and urbanization in francophone West Africa: a review of the recent empirical evidence, Urban Studies 41(11), 2004, pp. 2245-72; Beauchemin, C., Rural-Urban Migration in West Africa: Towards a Reversal? Migration Trends and Economic Situation in Burkina Faso and Côte d’Ivoire, Population, Space and Place 17(1), 2011, pp. 47-72; and the work of the Africapolis team working on the global e-Geopolis project to map and estimate populations for all the urban settlements in the world.

3 The UN Department of Economic and Social Affairs produces the “World Urbanization Prospects” used by many analysts. Its 2006 published estimates were compared with datasets for West African countries in Africapolis (AFD-SEDET, 2008).

4 Potts, D., Challenging the Myths of Urban Dynamics in Sub-Saharan Africa: The Evidence from Nigeria, World Development (2012).

5 For details on data sources see Potts, D., “Urban lives: adopting new strategies and adapting rural links” in Rakodi, C. (ed.), The Urban Challenge in Africa: Growth and Management of its Large Cities (United Nations University Press, 1997), pp. 447-94.