🌱 Birth rates
Often higher in lower-income countries and lower in high-income countries. Some countries have such low birth rates that they struggle to replace their population.
Population » Birth Rates, Death Rates and Migration
What you'll learn this session
Study time: 30 minutes
Cambridge spec: 5.3.1
- What birth rate, death rate and net migration mean
- How to work out natural increase and the change in population
- How these rates differ between countries
- The reasons why they differ, including push and pull factors
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Unlock This CourseThree rates that change a population
A country's population goes up or down for only three reasons: people are born, people die, and people move in or out. Economists measure each one as a rate, so that large and small countries can be compared fairly.
Key terms:
- Birth rate: the number of live births per 1,000 people in the population in one year.
- Death rate: the number of deaths per 1,000 people in the population in one year.
- Natural increase: the birth rate minus the death rate. If it is negative, the population falls naturally.
- Immigration: people moving into a country to live there.
- Emigration: people leaving a country to live somewhere else.
- Net migration: immigration minus emigration. It is positive when more people arrive than leave, and negative when more leave than arrive.
Working out the change
Population change has two parts: natural increase and net migration. A country can grow because of either one, or both.
Worked example
Country Zalmar (made up) has a population of 1 million, a birth rate of 20 per 1,000 and a death rate of 8 per 1,000. Natural increase = 20 − 8 = 12 per 1,000. For 1 million people that is 12 × 1,000 = 12,000 more people. In one year 30,000 people move in and 18,000 people move out, so net migration = 30,000 − 18,000 = +12,000. Total change = 12,000 + 12,000 = +24,000 people. Zalmar's population is growing from both sources.
A country can have a positive natural increase but negative net migration. Its population then grows or shrinks depending on which of the two is bigger.
How the rates vary between countries
These rates are not the same everywhere. In general:
⚠️ Death rates
Often higher where healthcare is poor. But a rich country with many elderly people can also have a fairly high death rate, because older people are more likely to die.
Net migration varies too. Some countries have strong positive net migration because many people want to live and work there. Others have negative net migration because many of their people leave to find work.
Reasons why birth rates vary
🏥 Healthcare
Where babies and children are more likely to die, families may have more children. Better healthcare means most children survive, so families often have fewer.
🎓 Education of women
Educated women often choose to work and have careers, and may start families later and have fewer children.
💰 Cost of raising children
Where children are expensive (housing, schooling, childcare), families tend to have fewer of them.
🙏 Culture and religion
Some cultures and religions value large families. Others accept smaller families more easily.
💵 Pensions
Where there are no pensions, parents may rely on their children to look after them in old age, so they may have more children. Good pensions reduce this need.
💊 Contraception
Where contraception is easy to get, families can choose how many children to have, and birth rates tend to be lower.
Reasons why death rates vary
Death rates are lower where there is good healthcare, clean water, enough food and good housing. They are higher where these are missing, or where there is conflict. The age of the population matters too: a country with many old people will have more deaths each year than a country with mostly young people, even if its healthcare is excellent.
Reasons why net migration varies
People move because of push factors (things that push them out of their home country) and pull factors (things that attract them to another country).
🚪 Push factors
Unemployment, low wages, poor healthcare or education, conflict, or natural disasters in the home country.
🌟 Pull factors
Job opportunities, higher wages, better healthcare and education, safety, or family already living there.
A country with strong pull factors tends to have high immigration. A country with strong push factors tends to have high emigration. For how easily workers move between places, see the lesson Mobility of Labour.
Common mistakes
Common mistakes
- Saying birth rate is the total number of births. It is births per 1,000 people, so it allows fair comparison.
- Mixing up immigration (in) and emigration (out). Think: Emigration = Exit.
- Forgetting that net migration is a difference. A country with lots of immigration can still have negative net migration if even more people leave.
- Giving only one reason. Strong answers give a reason AND explain how it changes the rate.
Exam-style question
Country Dorvia (made up) has a high birth rate and a falling death rate. Many young people are leaving to find work abroad.
(a) Define net migration. [2 marks]
(b) Explain two reasons why the birth rate in a country may be high. [4 marks]
(c) Analyse how push and pull factors may cause people to emigrate from Dorvia. [4 marks]
Model answer
(a) Net migration is the difference between the number of people moving into a country (immigration) (1) and the number leaving it (emigration) (1).
(b) Poor healthcare may mean children are more likely to die, so families have more children to make sure some survive (1+1). No pension system means parents rely on children to support them in old age, so they have larger families (1+1).
(c) A push factor such as unemployment or low wages in Dorvia means young people cannot earn enough at home (1). A pull factor such as higher wages or more jobs abroad attracts them to other countries (1). Together these cause people to emigrate (1), so Dorvia's emigration rises, which lowers its net migration (1).
Exam tip
In part (c), name one push factor and one pull factor, then link them to emigration. Naming both is what earns the full marks.