The World Population: Distribution, Density and Growth

Where the world’s people live and why, density, birth and death rates, natural and actual growth, push and pull factors of migration and demographic transition.

Key ideas

About 90% of the world’s people live on about 10% of its land; the ten most populous countries hold about 60% of them.
Geographical factors (water, landforms, climate, soils) and economic factors (minerals, urbanisation, industrialisation) decide where people live.
Population changes through births, deaths and migration.
Push factors (unemployment, poor living conditions, disasters, epidemics) drive people out; pull factors (jobs, better living conditions, security, a pleasant climate) draw them in.
Demographic transition: Stage I has high births and deaths; in Stage II deaths fall while births stay high, so population grows fastest; in Stage III both are low.
Malthus (1798) argued that population grows faster than the food supply.

Remember

Density	population ÷ area (persons per sq km)
Crude birth rate	live births ÷ mid-year population × 1,000
Crude death rate	deaths ÷ mid-year population × 1,000
Natural growth	births − deaths
Actual growth	births − deaths + in-migration − out-migration
Growth rate	(new population − old) ÷ old × 100

Watch out

Dividing area by population for density (population goes on top).
Adding out-migration instead of subtracting it in actual growth.
Giving a crude rate per 100 instead of per 1,000.

Worked example

Suppose a district’s population grew from 344,000 to 371,520 between two censuses. What is the growth in numbers, and the growth rate?

Working: 371,520 − 344,000; ÷ 344,000 × 100

Answer: 27,520 people; 8%