11.4 Characteristics of countries at different levels of development
- Syllabus
- 9708–2026–2027
- Topic
- 11.4
- Level
- A2
Learning objectives
11.4.1Population growth and structure• Population growth and structure:- measurement and causes of changes in birth rate, death rate, infant mortality and net migration- optimum population- level of urbanisation11.4.2Income distribution• Income distribution:- calculation of Gini coefficient and Lorenz curve analysis11.4.3Economic structure• Economic structure:- employment composition: primary, secondary and tertiary sectors- pattern of trade at different levels of development
Population change must be measured before its structure can be evaluated
| Indicator | Standard measurement |
|---|---|
| Birth rate | Live births per year / total population x 1000 |
| Death rate | Deaths per year / total population x 1000 |
| Infant mortality rate | Deaths before age 1 / live births in the year x 1000 |
| Net migration | Immigrants - emigrants; net migration rate divides this by population x 1000 |
| Population change | Births - deaths + net migration (ignoring statistical adjustment) |
| Urbanisation level | Urban population / total population x 100 |
| Change | Important causes and structural effects |
|---|---|
| Birth/fertility falls | Female education/employment, contraception, urban child costs, pensions and lower infant mortality; youth share later falls |
| Death/infant mortality falls | Nutrition, sanitation, clean water, vaccines/healthcare and income; population may initially grow faster and later age |
| Net inward migration | Wage/job/security/education pull and conflict/poverty push; labour/AD/tax base rise but housing/services face pressure |
| Net outward migration | Remittances may improve current transfers, but brain drain/worker loss can reduce capacity |
| Longer life expectancy/ageing | Larger old-age dependency, health/pension demand and possible saving/labour-supply changes |
Optimum population is the population size that maximises real output/income per head given the current natural resources, capital and technology. Below it, more labour/specialisation may raise output per head; above it, congestion and scarce factors may lower it. Better technology, capital, productivity or usable resources shift the optimum upward; a higher birth rate alone does not.
Urbanisation rises through rural-urban migration, natural increase in towns and reclassification of settlements. It can improve agglomeration, jobs and service access, but rapid unplanned growth can create congestion, housing/infrastructure shortages, pollution and informal employment while rural areas lose workers.
A falling population-growth rate does not mean population is falling while the rate remains positive. Read absolute numbers separately from percentages, and distinguish total dependency/age structure from a single birth or death rate.
Lorenz geometry turns income shares into a Gini coefficient
A Lorenz curve plots the cumulative percentage of households/people, ordered poorest to richest, on the horizontal axis against their cumulative percentage of income (or wealth) on the vertical axis. The 45-degree line is perfect equality; the Lorenz curve lies on/below it.
Gini = A / (A + B)
A is the area between the equality line and Lorenz curve; B is the area under the Lorenz curve within the equality triangle. If source areas are labelled X and Y, identify geometry rather than letters: numerator is the inequality gap and denominator is the whole triangle below equality.
| Change | Interpretation |
|---|---|
| Curve moves closer to equality line | Distribution becomes more equal; Gini falls toward 0 |
| Curve bows farther away | Distribution becomes more unequal; Gini rises toward 1 |
| Gini = 0 | Perfect equality in the measured distribution |
| Gini = 1 | Theoretical perfect inequality: one unit receives all measured income/wealth |
More progressive direct taxes, targeted transfers, minimum wages or broader education/asset access may reduce post-policy inequality; regressive indirect taxes, weaker inheritance/capital-gains taxation or long-term unemployment may increase it. The observed effect depends on behavioural responses and whether data are pre/post tax and income or wealth.
Gini measures relative distribution, not average income or poverty. Two countries can share a Gini with different Lorenz shapes and income levels, and wealth is usually distributed differently from income. State population, income definition, tax/transfer treatment and year before comparing.
Development changes employment sectors and the composition of trade
| Sector | Main activity | Examples |
|---|---|---|
| Primary | Extract/cultivate natural resources | Agriculture, fishing, forestry, mining |
| Secondary | Transform materials/build capital and structures | Manufacturing, processing, construction |
| Tertiary | Provide market/public services | Retail, transport, finance, health, education, tourism, digital services |
| Broad development pattern | Employment/productivity mechanism | Typical risk |
|---|---|---|
| Lower-income | High primary employment, often labour-intensive/subsistence and underemployment | Low productivity, volatile commodity income and limited formal jobs |
| Industrialising/emerging | Labour shifts toward manufacturing/construction and urban services; capital/skills raise productivity | Displacement, urban pressure, pollution and unequal regional gains |
| Higher-income | Lower primary employment share and larger/high-value tertiary plus advanced manufacturing | Service-sector size can hide low-paid work/deindustrialisation; output shares differ from employment shares |
| Development context | Common trade pattern | Consequences/conditions |
|---|---|---|
| Commodity-dependent lower-income | Export primary commodities; import machinery, manufactures and some services | Price volatility, deteriorating terms/foreign exchange risk; resource endowment can still generate high income |
| Industrialising | Rising manufactured exports, imported capital/intermediate inputs and participation in global value chains | Learning/jobs/export diversification versus import dependence and low value capture |
| Higher-income/diversified | More high-value manufactures/services, intra-industry trade, capital/technology and complex value-chain flows | Greater diversification but exposure to financial/service/global shocks |
Mechanisation can reduce agricultural employment while farm output rises; released workers may enter manufacturing/logistics. A falling primary employment share therefore does not prove primary output fell, and an expanding service share must be evaluated by productivity and job quality.
These are common patterns, not a ranking rule. Geography, natural resources, institutions, technology, policy and trade agreements can produce exceptions. Use sector shares and trade composition alongside income, productivity, informality and human-development evidence.