Cambridge O Level Economics: Differences in economic development between countries (2281)

This guide follows section 5.4 (5.4.1, differences in economic development between countries) of the Cambridge O Level Economics (2281) syllabus for examination in 2026, version 2. Tiers do not apply to this course. For each of seven areas you must be able to explain causes and impacts. Every country, sector and number below is invented and illustrative. None of it is a real statistic.

Related pages: the revision notes, the practice questions, the economic development practice set, the Cambridge O Level Economics hub, the printable checklist and the free diagnostics.

What 5.4.1 asks for

The syllabus lists seven areas. For each one, you explain what causes countries to differ and what difference it makes.

Area	Causes (why countries differ)	Impacts (what follows)
Income	Output, productivity, resources, stability	Living standards, saving, tax revenue
Productivity	Capital, skills, technology, health	Output, wages, competitiveness
Population growth	Birth and death rates, migration	Income per head, dependants, pressure on resources
Size of the three sectors	History, resources, investment, demand	Value added, jobs, stability of income
Saving and investment	Income, confidence, banks, government	Capital stock, future output
Education	Government spending, family income	Skills, productivity, earnings
Healthcare	Spending, clean water, medical staff	Working days, life expectancy, output

The areas are linked. Most exam answers gain credit by showing a link, for example that low income causes low saving, which causes low investment, which keeps productivity and income low.

Income

Income per head is total income (or output, GDP) divided by population. It is the usual starting point for comparing development, but it is an average. It hides inequality inside a country and says nothing about health, schooling or the environment.

Worked example 1: comparing two countries (illustrative)

Country K has GDP of 48,000 million currency units and 12 million people. Country L has GDP of 330,000 million and 6 million people.

Income per head, K = 48,000 / 12 = 4,000
Income per head, L = 330,000 / 6 = 55,000
L / K = 55,000 / 4,000 = 13.75

A person in L has, on average, 13.75 times the income of a person in K.

Causes of the gap: differences in the other six areas below, plus natural resources, political stability, and how far the country trades with others.

Impacts of a low income: low spending on food, housing, health and schooling, so living standards are low. People save little. The government collects little tax, so it cannot easily pay for hospitals, roads and teachers. This can trap a country in a loop in which poverty feeds on itself.

Productivity

Productivity measures how much is produced from each unit of a resource used. For labour, divide output by the number of workers or hours.

Output per worker, K = 48,000 million / 5 million workers = 9,600
Output per worker, L = 330,000 million / 3 million workers = 110,000

L’s workers produce about 11.5 times as much each, so a high income per head follows.

Causes of differences: more capital per worker (machines, buildings), better technology, better education and training, better health, better management, and a more suitable mix of industries.

Impacts of higher productivity: more output from the same workforce. Employers can pay higher wages without raising prices. Firms become more competitive against foreign producers, so exports can grow.

If output per worker in K rose from 9,600 to 10,560, the change is (10,560 − 9,600) / 9,600 × 100 = 10%. With the same workers, output rises by 10%.

Population growth

Population growth comes from the birth rate, the death rate and net migration. Compare growth in total output with growth in population.

Worked example 2: why fast population growth can slow income per head

Country K’s GDP grows by 3.0% a year and its population by 2.5%. Country L’s GDP grows by 2.4% and its population by 0.4%.

Growth in income per head, K = 1.030 / 1.025 - 1 = 0.49% (about 3.0 - 2.5 = 0.5)
Growth in income per head, L = 1.024 / 1.004 - 1 = 1.99% (about 2.4 - 0.4 = 2.0)

After ten years at these rates, K’s income per head is about 4,199 (from 4,000) and L’s is about 66,992 (from 55,000). The gap in absolute terms widens from 51,000 to about 62,793. K has the faster GDP growth but the slower growth in income per head.

Causes of higher growth: a high birth rate (children as workers, limited contraception, little female education, high child death rates), a falling death rate as health improves, and immigration.

Impacts: a large young population means many dependants for each worker, so the government must spend heavily on schools and the family has less to save. More workers can also be an advantage if there are enough jobs and enough capital for each of them. With too little capital, extra workers lower output per worker and raise unemployment.

Size of the primary, secondary and tertiary sectors

The primary sector takes output straight from nature: farming, mining and fishing. The secondary sector turns materials into goods and structures. The tertiary sector supplies services such as banking, transport, retail and health.

Worked example 3: sector shares in Country K (illustrative)

Sector	Workers (million)	Output (million)	Share of workers	Share of output	Output per worker
Primary	2.50	13,900	50%	29.0%	5,560
Secondary	0.75	9,600	15%	20.0%	12,800
Tertiary	1.75	24,500	35%	51.0%	14,000
Total	5.00	48,000	100%	100%	9,600

Half the workers produce under 30% of output. If 0.5 million workers moved from primary to secondary and matched that sector’s output per worker, output would rise by 0.5 × (12,800 − 5,560) = 3,620 million, or 7.5% of GDP.

Causes of differences: countries rich in land or minerals often start with a large primary sector. Others grow a secondary sector through investment and trade. As incomes rise, people spend a larger share on services, so the tertiary sector grows.

Impacts of a large primary sector: output per worker is often low, and incomes depend on weather and world prices, so they fluctuate. Raw materials usually sell for less than the finished goods made from them. Impacts of a larger secondary and tertiary share: higher value added, more varied jobs and steadier incomes. Moving out of farming needs capital, skills and roads, so structural change takes time.

Saving and investment

Saving is income not spent. Banks lend savings to firms, which invest in capital goods. Investment raises the capital stock, productivity and future output.

Worked example 4: investment per worker (illustrative)

Country K invests 10% of GDP. Country L invests 26%.

K: 10% of 48,000 = 4,800 million; per worker 4,800 / 5 = 960
L: 26% of 330,000 = 85,800 million; per worker 85,800 / 3 = 28,600

Each worker in L gets about 30 times as much new capital as a worker in K each year, so the capital gap widens over time.

Causes of low saving and investment: low incomes leave little to save. Families spend on necessities and may keep wealth in cash or gold, not in banks. Weak banks, high inflation, political risk and poor infrastructure deter firms from investing. The government may borrow funds that firms would have used.

Impacts: low investment means low capital per worker, low productivity and low growth. Countries may rely on foreign investment, and the profits then leave the country.

Education

Causes of differences: the amount the government spends on schools, whether families can afford fees and uniforms, whether children must work, and the number of qualified teachers. In Country K the government spends 3% of GDP on education (1,440 million) for 3 million pupils, which is 480 each. In L it spends 5% of GDP (16,500 million) for 1.1 million pupils, which is 15,000 each.

Impacts: an educated workforce learns new methods faster, uses machines properly and earns more. Educated people may start businesses and attract foreign firms that need skills. Better-educated parents tend to have fewer children and invest in their health. In a country with little education, firms struggle to find skilled staff and wages stay low. Some educated workers emigrate (brain drain), which loses the benefit of the state’s spending.

Healthcare

Causes of differences: government spending on hospitals, clinics and doctors, clean water and sanitation, food supply, and income to pay for private care.

Worked example 5: lost working time (illustrative)

In Country K, workers lose on average 15 of 250 working days a year to illness. In L they lose 5.

K: 15 / 250 = 6% of working time lost; 5 million x 0.94 = 4.7 million effective workers
L: 5 / 250 = 2%

If lost time reduces output in proportion, K loses 6% of 48,000 million, which is 2,880 million.

Impacts: healthy workers work more days, concentrate better and live longer, so skills are used for longer. Poor health reduces productivity, lowers school attendance, raises family spending on medicine and reduces saving. Better health also lowers child death rates, which in time can reduce birth rates.

Evaluating causes of differences

Examiners ask for a judgement, not just a list. Build a chain, then weigh it.

1. State a cause (low investment).
2. Explain the link (less capital per worker, so lower productivity).
3. State the impact (lower income per head).
4. Qualify it: how large, how quickly, and compared with what.

Weighing the causes. Education and health raise the quality of labour, but need government spending. Investment raises capital, but needs saving. Many factors reinforce each other, so a single “main cause” is hard to prove. A reasonable judgement picks one factor, explains why it comes first in a given case (for example, a country with a healthy workforce but no capital needs investment first) and admits that the others still matter.

Common errors

• Describing income per head as if it showed how income is shared. It is an average.
• Treating population growth as always harmful. Effects depend on jobs, capital and age structure.
• Writing that “primary goods are worthless”. They matter, but their prices fluctuate and they add less value.
• Naming a cause with no link to the impact.
• Mixing up GDP growth with growth in income per head.
• Stating a cause only. The syllabus asks for impacts too.

Official syllabus

Cambridge O Level Economics 2281 syllabus for examination in 2026, version 2, published by Cambridge University Press & Assessment (Cambridge International Education).