[1.2.5a] Labour demand & supply

The Labour Market

The labour market brings together employers (who demand labour) and workers (who supply it). It is analysed using supply and demand, with the wage rate on the vertical axis and the quantity of labour on the horizontal axis. Equilibrium determines the market wage (W*) and employment level (Q*).

Demand for Labour

The demand for labour is a derived demand — firms hire workers to produce goods and services, so demand for labour depends on consumer demand for the final product. Three key factors determine how much labour firms demand:

  • Demand for the final product: if consumer demand for a product rises, firms need more workers to produce it — labour demand shifts right. A fall in product demand shifts it left.
  • Availability of substitutes (including machines): if capital (machinery, automation) can replace labour more cheaply, firms substitute capital for labour, shifting demand left. Where labour is cheaper relative to capital, demand rises.
  • Productivity of the workforce: more productive workers generate more output per hour, making them more valuable. Rising productivity shifts labour demand right — each worker is worth more to the employer.

Supply of Labour

The supply of labour is determined by how many people are willing and able to work at a given wage. Eight key factors shift the labour supply curve:

FactorEffect of an increase
Population sizeLarger population → more potential workers → supply shifts right
MigrationNet immigration → more workers → supply shifts right; emigration shifts left
Age distributionMore working-age adults → supply shifts right; ageing population shifts left
Retirement ageHigher retirement age → workers stay in labour force longer → supply shifts right
School-leaving ageLower school-leaving age → more young workers enter earlier → supply shifts right
Female participationHigher participation rates → more workers → supply shifts right
Skills and qualificationsMore skilled workers → supply shifts right in skilled labour markets
Geographic/occupational mobilityGreater mobility → workers move where needed → supply in those markets shifts right

The Labour Market Diagram

Quantity of Labour (Q) Wage Rate (W) DL SL W* Q* DL₂ W₂ Q₂ Demand rises → W rises, Q rises

When labour demand increases (DL → DL₂), both the equilibrium wage and employment level rise to W₂ and Q₂. A fall in demand, or a rise in supply, shifts the relevant curve and the new equilibrium is read directly from the diagram.

 Key Takeaways

  • The demand for labour is a derived demand — driven by product demand, worker productivity, and availability of substitutes.
  • Labour supply depends on population, migration, age, participation rates, skills and mobility.
  • Equilibrium determines market wage (W*) and employment level (Q*).
  • A rise in labour demand → higher wages and more employment; a rise in labour supply → lower wages but more employment.
a) Factors affecting the demand for labour: • demand for the final product (derived demand) • availability of substitutes, including machines • productivity of workforce. b) Factors affecting the supply of labour: • population size • migration • age distribution of population • retirement age • school-leaving age • female participation • skills and qualifications • ability to move geographic locations/move to different types of employment. e) The use of labour market diagrams showing: • supply of labour, demand for labour, market equilibrium wage and quantity of labour (employment) • effect of shifts in demand for labour and supply of labour.