Population structure Revision Notes

Population structure refers to the composition of a population in terms of age groups and sex. It is crucial because it influences a country’s workforce, dependency ratios, and demand for services such as education and healthcare.

Age groups are typically divided into young (0-14 years), working-age (15-64 years), and elderly (65+ years). The sex ratio shows the number of males relative to females in each age group.

Population pyramids are visual representations that display this structure, with males on one side and females on the other, arranged by age cohorts from youngest at the base to oldest at the top.

• Population structure = age + sex distribution.
• Age groups: young (0-14), working-age (15-64), elderly (65+).
• Population pyramids graphically show these distributions.

In More Economically Developed Countries, population pyramids tend to have a narrower base and a wider top. This shape reflects low birth rates and low death rates, resulting in a stable or slowly growing population with a significant proportion of elderly people.

For example, countries like Germany or Japan have pyramids that look more rectangular or even top-heavy, indicating an ageing population. This is due to better healthcare, nutrition, and family planning, which increase life expectancy and reduce fertility rates.

The implications include increased demand for healthcare and pensions, and potential labour shortages as the working-age population shrinks relative to dependents.

• Narrow base = low birth rates.
• Wider top = high life expectancy, ageing population.
• Stable or slow population growth.
• Examples: Germany, Japan.
• Challenges: healthcare, pensions, workforce shortages.

Less Economically Developed Countries typically have population pyramids with a broad base and a narrow top. This shape indicates high birth rates and high death rates, especially among older age groups, resulting in a youthful population.

For instance, countries like Nigeria or Afghanistan show pyramids with a very wide base, reflecting many children, and a sharp tapering towards the top due to lower life expectancy.

This youthful population creates pressure on resources such as education and employment opportunities, and high dependency ratios with many young dependents.

• Broad base = high birth rates.
• Narrow top = lower life expectancy.
• Rapid population growth.
• Examples: Nigeria, Afghanistan.
• Challenges: education, jobs, resource allocation.

The differences between MEDCs and LEDCs arise from variations in birth rates, death rates, and life expectancy.

In MEDCs, widespread access to contraception, higher female education, and urbanisation reduce birth rates. Advanced healthcare reduces death rates and increases life expectancy.

In LEDCs, limited access to healthcare and family planning, higher infant mortality, and different cultural norms contribute to high birth and death rates, lowering life expectancy.

• MEDCs: low birth/death rates, high life expectancy.
• LEDCs: high birth/death rates, low life expectancy.
• Factors: healthcare, education, culture, economy.

Population structure affects economic development and social services planning.

In MEDCs, ageing populations increase demand for healthcare and pensions, and may require policies to encourage higher birth rates or immigration to maintain the workforce.

In LEDCs, youthful populations require investment in education, job creation, and healthcare to reduce infant mortality and improve life expectancy, supporting future economic growth.

• MEDCs: ageing population challenges.
• LEDCs: youthful population challenges.
• Planning for healthcare, education, employment.
• Policy responses vary by population structure.