Economic Structure (Cambridge International A-Level Economics)

Employment in primary, secondary and tertiary sectors

• Primary sector is defined as economic activity involving the direct extraction or harvesting of natural resources - including agriculture, fishing, forestry, mining and quarrying
• Secondary sector is defined as economic activity involving the processing of raw materials and the manufacture of goods - including construction, manufacturing and energy production
• Tertiary sector is defined as economic activity involving the provision of services- including retail, finance, transport, healthcare, education and tourism
• Some classifications also identify a quaternary sector covering knowledge-intensive activities such as research and development, information technology and consultancy, though this is not required at this syllabus level

Employment composition and level of development

• The share of employment in each sector changes predictably as an economy develops - this pattern is sometimes referred to as the structural transformation of an economy
• Low-income economies are typically characterised by a large primary sector, particularly subsistence and smallholder agriculture, which may account for 50–80% of employment

• As economies industrialise, employment shifts from the primary to the secondary sector

  • Manufacturing absorbs rural labour moving into cities, raising productivity and wages

• Advanced high-income economies are dominated by the tertiary sector, which typically accounts for over 70% of employment

  • The primary sector shrinks to a very small share as agricultural productivity rises and manufacturing relocates or automates

Limitations of the three-sector model

• The boundaries between sectors are not always clear

  • Agro-processing sits between primary and secondary
  • Financial services linked to commodity exports blur further distinctions

• Employment shares do not capture productivity differences

  • A small but highly productive agricultural sector in a high-income economy contributes more value per worker than a large low-productivity sector elsewhere

• The informal economy, which is large in low-income countries, is often underrepresented in official employment statistics, distorting apparent sector shares

Worked Example Which row shows characteristics of a fast-growing economy?

	GDP per capita	Birth rate	Household saving ratio
A	falling	falling	rising
B	falling	rising	falling
C	rising	falling	rising
D	rising	rising	falling

Final answer: Answer: C

• Option C correctly combines rising GDP per capita with falling birth rate and rising saving ratio - the classic profile of a mid-development economy in structural transformation
• A fast-growing economy would see rising GDP per capita as output expands faster than population — this eliminates options A and B immediately

Worked solution

• Between C and D, the key distinction is the birth rate and saving ratio: a fast-growing economy undergoing structural transformation typically experiences a falling birth rate (as urbanisation and female education rise) and a rising household saving ratio (as incomes grow and households accumulate capital for investment)
• Option D is incorrect — rising birth rates are associated with lower-income, pre-industrial economies; a fast-growing economy typically already shows demographic transition with birth rates declining

Pattern of trade at different levels of development

• The composition and direction of a country's trade changes significantly with its level of development

  • This reflects shifts in factor endowments, productivity, and comparative advantage

Low-income economies

• Trade is typically dominated by primary commodity exports - agricultural products, minerals, timber and fuels - which are produced using the abundant factor of unskilled labour and natural resources
• Imports tend to consist of manufactured goods, capital equipment and technology that cannot be produced domestically
• This pattern creates vulnerability to commodity price volatility - primary commodity prices are subject to large swings, meaning export revenues and government income can be highly unstable

Middle-income economies

• As industrialisation proceeds, the export mix shifts towards labour-intensive manufactured goods - clothing, footwear, basic electronics and assembled products
• Export earnings become more stable and less dependent on a single commodity
• Imports shift towards more sophisticated capital goods, intermediate inputs and services required for further industrial development
• Countries may pursue export-led growth strategies - actively orienting manufacturing towards global markets as a driver of income growth; South Korea, Taiwan and Vietnam are frequently cited examples

High-income economies

• Trade is dominated by high-value manufactured goods and knowledge-intensive services, such as financial services, insurance, business consulting, software and intellectual property
• Intra-industry trade becomes significant - countries both export and import similar categories of goods, reflecting product differentiation and economies of scale rather than simple factor endowments
• Trade in services grows as a share of total trade - in the most advanced economies services can account for a larger share of export earnings than goods

Key implications of trade pattern differences

Case Study Nigeria vs South Korea Pattern of trade at different levels of development

The context

Nigeria and South Korea had broadly comparable GDP per capita in the early 1960s. Over the following six decades their trade patterns diverged dramatically, making them a compelling contrast between commodity-dependent and export-led industrial development.

Actions taken

• Nigeria remained heavily reliant on oil exports following the discovery of crude oil in the late 1950s - by the 2010s petroleum accounted for over 90% of export earnings, with manufactured goods and services contributing very little
• South Korea pursued a deliberate export-led industrialisation strategy from the 1960s, shifting from low-value exports such as textiles into electronics, shipbuilding, steel and automobiles through targeted industrial policy and investment in human capital

Outcomes

• Nigeria's trade pattern remains characteristic of a low-income commodity exporter - high dependence on a single primary export, vulnerability to oil price volatility, and persistent importation of manufactured goods and capital equipment

• South Korea's export mix transformed entirely

  • It now exports high-value manufactures and technology products, with Samsung and Hyundai among the world's leading exporters in their sectors

• South Korea's GDP per capita reached over $33,000 by 2023; Nigeria's remained below $2,100

  • This illustrates how trade pattern and development level reinforce each other over time

Exam Hint The structural transformation from primary to secondary to tertiary employment is one of the most frequently tested development concepts - always link sector shifts to rising productivity, urbanisation and changing comparative advantage rather than describing them as automatic.

For trade pattern questions, the strongest evaluation point is that the pattern of trade reflects but also reinforces development levels:

• commodity dependence traps low-income economies in a low-value-added export structure
• while export-led industrialisation requires deliberate policy to shift up the value chain.