Population Growth and Age Structure
A country's population changes through births, deaths and migration, and the balance between those three leaves an age structure behind: some countries mostly young, others mostly old. The structure decides what the country has to plan for.
What a learner can do afterwards
- Name the three things that change a population's size: births, deaths and migration
- Read an age-structure chart and say whether the country is mostly young or mostly ageing
- Give one thing a young population has to plan for and one thing an ageing population has to plan for
- Explain why birth rates usually fall as incomes and schooling rise
1 · Read
Three forces change any population: births add people, deaths subtract them, and migration moves them across borders. Learn the three as a chant, because every later answer hangs off them. Earth passed seven billion around 2011 and passed eight billion in 2022.
Read an age chart by its shape. A wide base means many children and fast future growth. A narrow base with a thick top means an ageing country. Shape tells the story at a glance.
A young country must plan for schools and jobs for its children. An ageing country must plan pensions, care, and support for its elderly. Money troubles can strike late too: after the 2008 crash, some who planned calm retirements faced thin years.
Remember that birth rates usually fall as incomes and schooling rise. Richer, better schooled societies tend to have fewer children. Link each rate you quote to income or schooling before you conclude.
Births, deaths, and migration shape the age chart, and the chart sets the plans.
2 · Watch
Take it off screen
Where it sits
This opens up
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.