Birth rate, death rate & natural change

Population change is measured with rates per 1,000 people per year so countries of different sizes can be compared:

• Crude birth rate — the number of live births per 1,000 people in a year.
• Crude death rate — the number of deaths per 1,000 people in a year.
• Natural change — birth rate minus death rate. If births exceed deaths there is natural increase; if deaths exceed births there is natural decrease.

Natural change ignores migration — it only counts births and deaths already in a country.

Your turn — natural change

The 5 stages of the DTM

The Demographic Transition Model (DTM) shows how birth and death rates — and therefore total population — change as a country develops through five stages:

• Stage 1 — High fluctuating: high birth rate, high death rate, population low and stable.
• Stage 2 — Early expanding: death rate falls (better food, water, medicine) while birth rate stays high — population grows rapidly.
• Stage 3 — Late expanding: birth rate falls (contraception, women working, fewer children needed) — growth slows.
• Stage 4 — Low fluctuating: low birth rate, low death rate, population high and stable.
• Stage 5 — Declining: birth rate drops below death rate — natural decrease and an ageing population.

Why does population grow fastest in Stage 2?

Reading a population pyramid

A population pyramid shows the number of males and females in each age group. Its shape tells you about a country's stage of development:

• LEDC pyramid — wide base (high birth rate, many children) and narrow top (short life expectancy). This creates youth dependency.
• MEDC pyramid — narrow base (low birth rate) and a wide top (long life expectancy). This creates aged dependency.

What dependency means

The dependent population is under 15 or over 64 — too young or too old to work. The working population (15–64) supports them. The dependency ratio compares the two.

• Aged dependency (MEDC): higher pension and healthcare costs, pressure on the working population, but skilled experienced workers and possible labour shortages.
• Youth dependency (LEDC): high spending on schools, healthcare and food for children; but a large future workforce once they grow up.

Formula: dependency ratio = (dependent population ÷ working-age population) × 100.

Your turn — dependency ratio

Effects on both areas

Migration affects the place people leave (the source) and the place they arrive (the host):

• Source area: loses young workers (a "brain drain"), but gains money sent home (remittances) and less pressure on jobs.
• Host area: gains workers to fill labour shortages and a richer mix of cultures, but may face pressure on housing, schools and services.

Push & pull factors

Migration is the movement of people to live in a new place. It is driven by two forces:

• Push factors drive people away from an area: war, unemployment, poverty, natural disasters, persecution, poor services.
• Pull factors attract people to an area: jobs, higher wages, safety, better schools and hospitals, joining family.

Barriers can block migration: physical barriers such as mountains, deserts or seas, and human barriers such as visa rules, border controls, cost and language.

Sort each statement

Tap a statement, then tap the group it belongs to.

Your turn — natural decrease

Economic migrant vs refugee

The reason for moving decides the legal category:

• Economic migrant — moves by choice, mainly to find work or a higher standard of living. This is voluntary migration.
• Refugee — forced to flee their country to escape war, persecution or disaster and cannot safely return. An asylum seeker is someone who has applied for refugee status but is awaiting a decision.

Case study flag: CCEA uses an example such as Syrian refugees arriving in Greece. Check any specific numbers of arrivals, dates or routes against your class notes before quoting them — do not rely on memory for the figures.

Migrant or refugee?

Match each term to its meaning

Tap a term on the left, then its matching meaning on the right.

Which is a physical barrier?

Which pyramid is which?

The big ideas to know

You've covered all of CCEA Theme A — Population & Migration. Press Finish to see your score.