Population in Rwanda

Lessons

Senior 4 · Geography

Population in Rwanda

4 lessons

Lesson 3 of 4

Population Structure and Population Growth: Causes, Effects and Solutions

25 min

A pyramid with a wide base

Figure 5 shows every resident of Rwanda in 2022, sorted by age and sex. Before reading on, describe its shape: how wide is the base compared with the top? Where does it narrow fastest? Are there more males or females at the top?

Figure 5. Age-sex pyramid of Rwanda, 2022, drawn by Ganzaa from NISR, RPHC5 Table 5.

Definition

Population structure (composition): how a population is divided by age and sex. Age-sex pyramid: a pair of horizontal bar charts showing the share of males and females in each age group.

Dependency ratio: dependants (under 15 and 65 and over) per 100 people of working age (15–64):

\text{DR} = \frac{P_{0\text{–}14} + P_{65+}}{P_{15\text{–}64}} \times 100

Sex ratio: males per 100 females. Population momentum: continued growth because a large young generation is entering child-bearing age, even after fertility falls.

Worked example 1: reading the structure in numbers

Data (NISR, 2023). Under 15: 4,956,812. Aged 65 and over: 551,928. Total: 13,246,394. Males 6,429,326, females 6,817,068.

P_{15\text{–}64} = 13\,246\,394 - 4\,956\,812 - 551\,928 = 7\,737\,654

\text{DR} = \frac{4\,956\,812 + 551\,928}{7\,737\,654} \times 100 = 71.2 \qquad \text{sex ratio} = \frac{6\,429\,326}{6\,817\,068} \times 100 = 94.3

Interpretation. 37.4% of Rwandans are under 15 and only 4.2% are 65 or over, so every 100 people of working age support about 71 dependants, almost all of them children (youth dependency 64.1, old-age dependency 7.1). There are 94 males per 100 females; the female majority is largest at older ages, where women outlive men (life expectancy 71.2 against 67.7).

What the pyramid tells us

A wide base: high fertility in the recent past. The 0–4, 5–9 and 10–14 bars are about the same size, so births have stopped rising: fertility is falling while the number of mothers grows.
Steady narrowing upwards: fewer people survived to old age in the past, the "sign of high levels of mortality" noted by NISR.
A narrow top: few elderly; more women than men in old age.
Urban and rural differ: NISR notes that the urban pyramid is "more dominated by adult people in the working age group, a consequence of labour migration from rural to urban areas" (lesson 4).

Figure 6. The demographic transition model (schematic), drawn by Ganzaa. Rwanda's 2022 rates place it in stage 3: the death rate is low, the birth rate is falling but still high.

Children play football on a village road in Kinigi, Musanze District, 31 July 2018. More than a third of Rwanda's people (37.4% in 2022) are under 15. Photo: Rebecca Johnson, CC BY-SA 4.0, via Wikimedia Commons.

Why the population grows fast

Factor	Evidence from the 2022 census
Fertility still above replacement	TFR 3.6 children per woman; 4.0 in the Eastern Province and 4.5 in Rusizi District
Falling mortality	CDR down from 17.1 (1978) to 6.3; infant mortality down from 49 (2012) to 28.9 per 1,000
Young age structure (momentum)	50.7% of the population (6.7 million) are women and men aged 15–49; 3,445,665 women of child-bearing age
Early child-bearing	13% of 19-year-old girls had already given birth
Education and residence	TFR 3.9 for women with primary education against 3.4 for secondary or above; lowest in Kigali (3.0)
Health care	Better vaccination, maternal and child care raise survival (life expectancy 69.6 years)

Worked example 2: why growth continues after fertility falls

Question. NISR projects that the population will grow from 13.2 million to 23.6 million by 2052 (medium scenario) even though fertility is falling. Explain.

Answer. In 2022 there were 1.71 million children aged 0–4 and 1.51 million young people aged 15–19, against 1.17 million aged 20–24 (Figure 5). The large cohorts under 20 will become parents over the next 30 years. Even with fewer children each, so many more parents mean many births: this is population momentum. Growth only stops when fertility has stayed near replacement for about a generation.

Effects of rapid population growth

Negative effects	Positive effects
Pressure on land: smaller farms, cultivation of steep slopes and wetlands, soil erosion	A large, young labour force
Rising demand for schools, health care, water and housing	A bigger home market for goods and services
Too few jobs for young job-seekers; urban unemployment	A possible "demographic dividend" if fertility falls and the many workers are educated and employed
Pressure on forests (fuelwood) and wildlife	Labour for public works such as terracing and umuganda
High dependency: savings and taxes are spread over many children	Pressure for innovation in farming and industry

Solutions

Family planning and reproductive health services, so that couples can choose the number and spacing of children.
Education, especially of girls: the census shows lower fertility with more schooling, and keeping girls in school delays first births.
Child health: when parents expect their children to survive, they choose fewer.
Non-farm jobs and urbanisation: the projections assume Rwanda's aim of 70% of the population living in towns by 2050 (NISR, 2023); urban fertility is lower (Kigali TFR 3.0).
Higher farm productivity: land consolidation, irrigation and better inputs so that land feeds more people (unit 11).
Sensitisation on the costs of large families, and laws that protect girls from early marriage and abuse.

Warning

A falling growth rate does not mean a falling population. Rwanda's growth rate fell from 2.6% to 2.3%, yet more people were added between 2012 and 2022 (2.73 million) than between 2002 and 2012 (2.39 million), because 2.3% of a bigger number is larger.

HRB Education: "Population Pyramids Explained". How to describe and interpret the shape of a pyramid. Apply the method to Figure 5 and decide which shape Rwanda's pyramid matches.

✦

Practice

Describe the shape of Rwanda's 2022 population pyramid.
Calculate the percentage of the population aged 65 and over (551,928 of 13,246,394).
A population has 4.2 million under 15, 0.4 million aged 65+ and 6.4 million aged 15–64. Calculate the dependency ratio.
Give three causes of rapid population growth in Rwanda, with census evidence.
Explain population momentum using Rwanda's age structure.
Suggest how the shape of the pyramid will change by 2052 if fertility keeps falling.
"Rapid population growth is the main obstacle to development in Rwanda." Discuss.

Show answersHide answers

A wide base (about 12–13% of people in each of the three youngest groups), narrowing steadily with age to a very narrow top; slightly more females than males, especially in old age: a young, "expansive" pyramid whose bottom three bars are nearly equal.
$\frac{551\,928}{13\,246\,394} \times 100 = 4.2\%$ .
$\frac{4.2 + 0.4}{6.4} \times 100 = 71.9$ .
Any three: TFR still 3.6 (4.0 in the East); falling death rates (CDR 6.3, IMR 28.9); a young structure with many women of child-bearing age; early child-bearing (13% of 19-year-olds); lower fertility only with more education.
Large cohorts born in the last 20 years (1.5–1.7 million per five-year group) are entering their child-bearing years; even with fewer children each, the number of births stays high, so the population keeps growing.
The base will narrow relative to the middle; the bulge of working-age adults will move up; the top will widen as more people survive to old age: the pyramid becomes more barrel-shaped.
Growth strains land, jobs and services and keeps dependency high. But development also depends on education, investment, governance, trade and technology; a young population can be an asset if educated and employed. A balanced conclusion: growth is a major challenge, not the only obstacle.

Quick check

Key points

Rwanda's 2022 pyramid is young: 37.4% under 15, 4.2% aged 65+; dependency ratio 71.2; sex ratio 94.3.
Rwanda is in stage 3 of the demographic transition: CDR 6.3, CBR 27.8 and falling.
Causes of growth: TFR 3.6, falling mortality, momentum, early child-bearing; fertility is lower with education and in towns.
Effects are both negative (land, jobs, services, environment) and positive (labour, markets, a possible dividend). Solutions: family planning, girls' education, child health, non-farm jobs and urbanisation, higher farm productivity.

Sources and credits

Source: Fifth Rwanda Population and Housing Census, 2022: Main Indicators Report, NISR, 2023 (age-sex structure, fertility, mortality, adolescent births, projections and the 70% urban aim).

Figures 5 and 6 and the worked examples were drawn and written by Ganzaa.

Photo: At play in Kinigi 01, Rebecca Johnson, CC BY-SA 4.0, via Wikimedia Commons.

Video: "Population Pyramids Explained: What They Show & How to Analyse Them", HRB Education, embedded from YouTube. The rest of the lesson and the exercises were written by Ganzaa.

This lesson adapts CC BY-SA material and is shared under CC BY-SA 4.0.

1A pyramid with a wide base

2What the pyramid tells us

3Why the population grows fast

4Effects of rapid population growth

5Solutions

A pyramid with a wide base

What the pyramid tells us

Why the population grows fast

Effects of rapid population growth

Solutions