How many people live in Africa, and how? At least one in three people has not been counted.

Until the end of 2023, Namibian authorities were working under the assumption that the country's population was approximately 2.6 million, of whom around 60% were young people under the age of 35. The figures they were considering were based on a projection made by the state statistics agency based on the just over two million inhabitants counted in a study more than a decade earlier.

The surprise came in March 2024, when the Namibian statistics agency released the preliminary results of the last population census conducted in the country just six months earlier. Contrary to the previously reported figure, Namibia's population was just over three million. So, overnight, 400,000 people—equivalent to 15% of the country—whom the state hadn't even known existed came to light.

The gap between the population estimate used by the Namibian authorities until the end of 2023 and the population figure revealed by its latest census highlighted the importance of conducting these types of demographic and health records regularly and rigorously, in order to plan public policies wisely and subsequently analyze their effectiveness. Ideally, according to the United Nations Statistics Division, these records should be conducted once every decade.

Namibia, however, is not an isolated case, but conducting these large-scale surveys is becoming increasingly difficult. The UN Economic Commission for Africa (ECA) notes that the 2020s census round, planned between 2014 and 2024, was affected by unforeseen events such as the pandemic, but also by more profound ones such as a lack of funding and a low response rate. Today, it is estimated that at least one in three Africans is uncounted, although some estimates put this figure as high as 45%.

You have to tell everyone because everyone counts.

Priscilla Idele, Chief of the Population and Development Branch of the United Nations Population Fund (UNFPA)

Priscilla Idele, head of the population and development branch of the United Nations Population Fund (UNFPA), acknowledges that censuses are a large and difficult task. But she warns that "while many censuses face universal challenges, those in Africa face more acute challenges." Nevertheless, Idele maintains that "everyone must be counted because everyone counts."

Public policies

There are many reasons for maintaining an accurate count of a country's population. One of the most notable is that having an accurate and up-to-date census allows authorities to properly plan for essential services such as healthcare, education, and basic infrastructure, including water and electricity supplies and public transportation, as it not only provides information on how many people there are but also where they live.

Other areas where this information is crucial are economic planning and urban development and housing policies, as they also capture population movements, usually to cities . This data is equally key for the allocation of funds from international financial institutions and cooperation agencies. Even more sensitive, it is used to adjust political representation, for example with the territorial allocation of seats.

“A census is perhaps the most important source of data a country can have,” Idele says. “It provides very comprehensive information about the entire population: the number of people in a country at a given time; where they live; the demographic structure, such as age and sex; their living conditions; population movements; and other socioeconomic characteristics, such as educational level or employment status,” she explains.

Beyond guiding public policy, population and health censuses provide data for research, whether in academia or for civil society. Practical examples include studies on the prevalence of people with disabilities in different areas of Senegal; estimates of household electricity use for lighting or cooking in Swaziland; and provincial-level infant mortality estimates in Burkina Faso.

Lorretta Ntoimo, a professor of social demography at the Federal University of Oye Ekiti in Nigeria who has researched the gender perspective of African demographic studies, highlights the importance of these data from this perspective. “The majority of decision-makers in the private and public spheres are men, who disproportionately benefit from the status quo. Research-based evidence is needed for them to accept this and implement policies that gradually reduce inequality,” she notes.

Growing challenges

The major leap forward for most African nations in collecting data through demographic and health censuses came in the 1980s, with 47 of the continent's 54 countries conducting them in the 2010 round, according to the US-based Population Reference Bureau (PRB) . For the 2020 round, which was due to end last year, the number had dropped to 41, according to the ECA's tally.

UNFPA estimates are more alarming. “If we add the uncounted people [estimated to live] in countries that didn't conduct the census, around 45% of the African population wasn't counted in the last round. This is because large countries like Nigeria, Ethiopia, and the Democratic Republic of the Congo [the three most populous on the continent] didn't conduct the census. So imagine how many people we still don't know,” Idele says.

One of the major factors that disrupted the last round of censuses was the pandemic. But the ECA lists other, deeper difficulties that have exacerbated this challenge and threaten to become even more acute: on the one hand, limited financial resources and, on the other, high non-response rates, mainly due to the complexity of reaching people in marginalized neighborhoods, on the move, and in crisis-affected areas.

Adding to all this is now a major setback, the result of President Donald Trump's January suspension of the United States Agency for International Development (USAID) . USAID funded the majority of a Demographic and Health Survey (DHS) program in more than 90 low- and middle-income countries—many in Africa—that has now been halted following its abolition in March.

Since its launch in 1984, DHS has contributed to more than 450 surveys, and its free database has informed hundreds of reports and thousands of scholarly articles. Its surveys also compiled information used to calculate some 30 indicators for the Sustainable Development Goals (SDGs) and the 2030 Agenda, including data on access to clean water, infant mortality, female genital mutilation , and domestic violence.

Based on surveys of African countries published by the DHS in 2024, we can see, for example, that the average age of women marrying in rural Senegal is less than 19 ; that only 16% of women in Mozambique know that abortion is legal ; that one in three women aged 15 to 49 has experienced physical violence in Ghana; and that there is a strong correlation between education levels and seeking help for depression in Lesotho.

Livia Montana, the program's technical director until its dissolution, asserts that one of DHS's greatest strengths was standardizing the survey's methodology and key health and demographic indicators. "If each country conducts its own independent survey, asking similar questions but in slightly different ways, you can't be sure the indicators are directly comparable," Montana laments.

Regarding survey response rates, the decline encountered by the 2020 census round on the continent is in line with a similar global trend . But William Muhwava, head of the ECA's population and youth section, points out that in Africa this is not due to a refusal to participate, but rather to the difficulties in covering territories at war or experiencing severe instability, particularly in the Sahel and the Horn of Africa, and the urban changes that occur between the time a territory is mapped and the census is conducted.

In some countries on the continent, such as South Africa, this trend is also explained by other factors, equally present in many Western countries, such as a decreasing willingness to participate in polls and a growing reluctance to share personal data, partly due to greater political polarization and greater distrust of the government.

In its latest census, in 2022, the percentage of uncounted people in South Africa—which became known after post-survey adjustments to correct errors—soared to 31%, the highest since apartheid. The main reasons cited for this were the impact of the pandemic, increased political violence, low trust in the government, and a previously downward response trend.

Room for improvement

Despite the challenges and bleak future prospects, experts emphasize that the 2020 census round in Africa was also characterized by the adoption of new technologies, which streamlined data collection and publication. “The transformation of manual systems into digital ones was the main achievement,” Muhwava believes.

Another positive change was the increased cooperation between countries on the continent, which made the process more efficient. “For example, the electronic tablets used [to collect data in] Malawi were used in Zambia; those used in Togo were shared with Namibia, Angola, and Gambia; those used in Kenya were [sent] to Mauritius and Sierra Leone; and those from Ghana were sent to Liberia,” explains Idele. The UNFPA expert notes that this “cooperation between countries in the South” made it possible to “reduce costs” and “learn lessons.”

Looking ahead, this commitment to technology is expected to be strengthened to address some of the challenges African countries face in conducting their censuses, including the use of artificial intelligence and satellite imagery to map population centers. Efforts are also being made to use other administrative data for census purposes, such as civil registration and information from ministries such as education, health, and labor. “There will be many more innovations, and they will make data collection easier, less expensive, more secure, and faster than before,” Idele believes.

Former DHS program team members are working on a new initiative to reestablish a core survey program to monitor DHS's work. "While it's unlikely to completely replace it, we hope the new initiative, with consortium members from around the world, will maintain the core elements of DHS while meeting countries' evolving data needs," Montana said.