Where to draw the line: Data problems and other difficulties estimating urbanisation in Africa

Figures & data

Table 1. Criteria for designation as an urban area in censuses in sub-Saharan Africa.

Type of definition	Parameters	Countries
Number of people in locality/agglomeration/town	An area is defined as urban if the population size is above a certain threshold^a	Angola, Benin, Côte d’Ivoire^d, Comores, Equatorial Guinea, Eritrea, Ethiopia, Benin, Ghana, Guinea-Bissau, Madagascar, Malawi, Mali, Mauritania, Nigeria, Senegal, Sierra Leone, Somalia, South Sudan
Mixed definition: number of people and economic activity	Minimum number of people^b and 50 to 75% of them engaged in non-agricultural economic activity	Botswana, Côte d’Ivoire, Democratic Republic of Congo, Zambia, Zimbabwe
Mixed definition: number of people and function of area	Minimum number of people^c and area is principle centre, municipality, town council, other urban centre or administrative headquarter	Central African Republic, Kenya^e, Niger, Uganda
Mixed definition: number of people and infrastructure	Localities of minimum 5 000–10 000 people and sufficient socio-economic and administrative infrastructure	Burkina Faso, Cameroon
Function of area	Administrative centres of prefectures, principle or district centres, capitals, district capitals, town planning areas	Cameroon, Chad, Comores, Côte d’Ivoire, Equatorial Guinea, Guinea, Guinea-Bissau, Malawi, Niger, Rwanda, Somalia, South Sudan, Togo
Mixed definition: function of area and economic activity	District headquarters and other settlements with rapid population growth and facilities that encourage people to engage in non-agricultural economic activities	Lesotho, Namibia
Places/localities officially designated as urban: Swaziland, Zimbabwe
Specific towns Burundi: Commune of Bujumbura
Cape Verde: as of 1990, municipalities of Praia, Mindelo, Sao Filipe and Espargos/Sal
Congo: as of 1984, six communes (Brazzaville, Pointe-Noire, Dolisie/Loubomo, Nkayi, Ouesso and Mossendjo)
Djibouti: for the 1956 and 1960 censuses, Djibouti (capital); for the 1983 census, the urban population of Ali-Sabieh, Dikhil, Tadjourah and Obock added; for the 1991 census, Arta, Damerjog, Yoboki and Randa added; for the 2009 census, Djibouti ville, and urban and rural sedentary populations of the regions of Ali Sabieh, Dikhil, Tadjourah, Obock and Arta added
Mozambique: for the 1980 census, 12 cities (Maputo, nine provincial capitals and the cities of Nacala-Porto and Chokwe); in the 1997 and 2007 censuses, 23 cities and 68 towns/vilas
Saint Helena: James Town (capital) and Half Tree Hollow
São Tomé and Príncipe: the district of Água Grande (São Tomé and Pantufo) and six other small settlements (as of 1991)
Other definitions Gambia: no official definition pre 1993 census; 2003 census states that a settlement is urban if it satisfies most of the following criteria: some commercial and institutional importance, non-agricultural work for most of the population, minimum 5000 people, high density, some degree of infrastructure
Mauritius: towns with proclaimed legal limits
Réunion: communes of minimum 2000 people living in houses no more than 200 m apart; or communes in which the majority are part of a multi-communal agglomeration
South Africa: classification is based on dominant settlement type and land use; cities, towns, townships, suburbs and so forth are typical urban settlements; enumeration areas with informal settlements, hostels, institutions, industrial and recreational areas, and smallholdings within or neighbouring a formal urban settlement are classified as urban
United Republic of Tanzania: 1957 and 1967 censuses, 16 gazetted townships; 1978 census onwards, definition includes several criteria, including regional and district headquarters, and wards with urban characteristics (exceed a minimal level of size-density criteria and/or many inhabitants in non-agricultural occupations); no specific numerical values of size and density identified; District/Regional Census Committees decide which wards are urban
No official definition: Seychelles, Mayotte

Source: United Nations World Urbanization Prospects: The 2014 Review (United Nations, 2015); McGranahan & Satterthwaite (2014); Tiffen (2003).

Notes: ^aDifferent minimum number of people for different countries, e.g. 1000, 1500, 2000, 2500, 3000, 5000, 10 000 or 20 000.

^bDifferent minimum number of people for different countries, e.g. 2000, 2500, 4000, 5000 or 10 000.

^cDifferent minimum number of people for different countries, e.g. 2000, 2500 or 3000.

^dSeveral countries have more than one set of criteria for defining their urban areas, so they appear under multiple categories in this table.

^eBecause of substantial changes in the 1999 census delineations of urban areas in Kenya, only the population for the ‘urban core’ should be considered to ensure consistency with previous censuses.

Table 2. Change in United Nations urban population projections to 2000 (thousands).

Country name	Projection for 2000 made in 1980		Projection for 2000 made in 1996		Percentage change in projections between 1980 and 1996
Democratic Republic of Congo	27 839		15 670		−45.4
Ghana	10 843		7 644		−29.5
Lesotho	217		641		195.4
Malawi	6 489		1 686		−74.0
Mozambique	3 199		7 869		146.0
Nigeria	45 041		55 561		25.8
South Africa	30 109		23 291		−22.4
Sudan	16 551		10 772		−34.9
Region	Mean percentage error^a			Mean absolute percentage error^a
	20 years	10 years	5 years	20 years	10 years	5 years
Sub-Saharan Africa	0.218	0.234	0.055	0.382	0.274	0.097

Source: Adapted from Brockerhoff (1999), Cohen (2004).

Notes: ^aTwenty-year comparison, United Nations projections for year 2000 in 1980 compared with United Nations data in 2001; 10-year comparison, United Nations projections for year 2000 in 1991 compared with United Nations data in 2001; five

-year comparison, United Nations projections for year 2000 in 1998 compared with United Nations data in 2001.

Table 3. Population distribution of the world by area and size class of urban settlement (millions).

Area of residence and size class	1970	1990	2014	2030
Minimum 10 million	55	153	453	730
5–10 million	106	157	301	434
1–5 million	245	459	827	1 128
500 000–1 million	129	202	363	509
<500 000	816	1 313	1 936	2 257
Total urban	1 351	2 284	3 880	5 058
Rural	2 341	3 036	3 364	3 367
Total population	3 692	5 320	7 244	8 425

Source: Adapted from United Nations (2015).

United Nations, Department of Economic and Social Affairs (DESA), Population Division, 2015. World urbanisation prospects: The 2014 Revision, report no. ST/ESA/SER.A/366. http://esa.un.org/unpd/wup/FinalReport/WUP2014-Report.pdf Accessed 11 November 2015.

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