Reasons why birth rates, death rates and net migration rates can vary between countries

Economic Development – Population

Learning Objective

Explain the reasons why birth rates, death rates and net migration rates can vary between countries.

1. Birth Rates

The birth rate is the number of live births per 1,000 people in a given year. Several factors influence its level:

• Economic development: Higher income levels often lead to lower birth rates because families can afford fewer children and invest more in each child's education and health.
• Education, especially of women: Increased female schooling correlates with delayed marriage and childbearing, reducing fertility.
• Access to contraception and family‑planning services: Availability and cultural acceptance lower unintended pregnancies.
• Cultural and religious norms: Societies that value large families or have religious teachings encouraging procreation tend to have higher birth rates.
• Urbanisation: Urban living costs and limited housing space discourage large families.
• Government policies: Pro‑natal incentives (e.g., tax breaks, child allowances) can raise birth rates, while policies such as China’s former one‑child policy reduced them.

2. Death Rates

The death rate is the number of deaths per 1,000 people in a given year. Key determinants include:

• Healthcare quality and accessibility: Nations with well‑developed health systems have lower infant and adult mortality.
• Nutrition and living standards: Adequate food, clean water, and safe housing reduce disease and mortality.
• Prevalence of disease: High rates of communicable diseases (e.g., malaria, HIV/AIDS) raise death rates, while effective vaccination programmes lower them.
• Age structure: Populations with a larger proportion of elderly people naturally have higher death rates.
• Environmental factors: Pollution, climate‑related disasters, and occupational hazards can increase mortality.
• Public safety and violence: High levels of conflict, crime, or road traffic accidents elevate death rates.

3. Net Migration Rates

Net migration is the difference between the number of people entering (immigrants) and leaving (emigrants) a country per 1,000 population. Influencing factors are:

• Economic opportunities: Higher wages, better employment prospects, and career advancement attract immigrants.
• Political stability and safety: Refugees flee conflict, persecution, or natural disasters, while stable countries receive them.
• Education and skill acquisition: Students and skilled workers migrate for higher education and specialised training.
• Family reunification policies: Nations that allow family members to join residents encourage migration.
• Legal and immigration frameworks: Restrictive visa policies deter immigration; liberal policies encourage it.
• Cost of living and quality of life: High living costs may push residents to emigrate, while attractive social services draw newcomers.

4. Comparative Summary

5. Illustrative Formula

The overall population change can be expressed as:

\$\Delta P = (B - D) + M\$

where:

• \$\Delta P\$ = change in population
• \$B\$ = number of births
• \$D\$ = number of deaths
• \$M\$ = net migration (immigrants minus emigrants)