Actual and potential growth, output gaps, the trade cycle, the causes and effects of growth, and its sustainability.

What this dot point is asking

WJEC wants you to distinguish actual from potential growth, explain output gaps and the trade cycle, analyse the causes and effects of growth, and evaluate its sustainability.

The answer

Actual and potential growth and output gaps

A negative output gap (actual output below potential) means there is spare capacity, with unemployed resources and low inflationary pressure, typical of a recession. A positive output gap (actual above potential) means the economy is operating beyond its sustainable capacity, with tight labour markets and rising inflationary pressure, typical of a boom. Distinguishing actual from potential growth matters because demand-side policy mainly affects actual growth (closing a negative gap), while supply-side policy raises potential growth (shifting LRAS right), and only the latter raises capacity in the long run.

The trade cycle and the causes of growth

In the short run, demand-side factors (rising consumption, investment, government spending or net exports) raise actual output, especially when there is spare capacity. In the long run, supply-side factors drive sustainable growth: investment in physical capital, a larger and more skilled workforce (education, training, migration), technological progress and improved efficiency all shift LRAS right and raise potential output. Sustained rises in living standards depend on productivity growth, which is why the UK's weak productivity performance is such a concern. The trade cycle means growth is uneven, with booms risking inflation and recessions raising unemployment.

The costs and sustainability of growth

Growth brings clear benefits: higher real incomes and living standards, lower unemployment, higher tax revenues to fund public services, and the means to reduce poverty. But it has costs: environmental damage and resource depletion, possible widening inequality if the gains are unevenly shared, inflationary pressure if growth is demand-led near capacity, and the social costs of rapid structural change. This is why sustainability matters: growth that runs down natural capital or drives climate change may not be sustainable, so economists increasingly judge the quality and type of growth, not just its rate. The balance of benefits and costs is the heart of the evaluation the exam expects.

Examples in context

Example 1. The UK productivity puzzle. UK output per worker has grown unusually slowly since the financial crisis, the "productivity puzzle". Because long-run living standards depend on productivity-driven potential growth, this weak performance limits how fast the economy can grow without inflation. It puts the spotlight on supply-side causes of growth, investment, skills, infrastructure and innovation, and explains why raising potential growth, not just managing demand, dominates UK growth policy.

Example 2. Green growth and sustainability. The drive to reach net-zero emissions reframes growth around sustainability: the aim is growth that does not deplete natural capital or worsen climate change. Investment in renewable energy and clean technology is presented as a route to growth that is both higher and more sustainable, while the costs of the transition illustrate the trade-offs. It is a live application of the idea that the type of growth matters as much as its rate.

Try this

Q1. Define a negative output gap. [2 marks]

• Cue. When actual output is below potential output, so there is spare capacity (unemployed resources and weak inflationary pressure).

Q2. Explain one supply-side cause of long-run economic growth. [3 marks]

• Cue. For example investment in physical capital, a larger or more skilled workforce (education, training, migration), or technological progress, each shifting long-run aggregate supply right and raising potential output.