AQA A-level Economics: Economic growth and the economic cycle (7136)

This guide covers the content point “Economic growth and the economic cycle” in the AQA A-level Economics (7136) specification, version 1.3 (29 June 2022). It is numbered 3.2.3.1 on the AQA website and appears as 4.2.3.1 in the combined AS and A-level PDF. The topic belongs to the national and international economy content, which is assessed in Paper 2 and can also appear in Paper 3. The specification does not mark any of it as AS-only or A-level-only.

Related pages: the course hub, the printable checklist, the revision notes, the practice set, the aggregate demand and supply guide and the free diagnostics.

All figures below are invented. Countries A to E are made-up economies used for illustration only.

What the specification asks for

Content	What you must be able to do
Short-run and long-run growth	Distinguish them with a production possibility curve (PPC) and AD/AS diagrams
Determinants	Explain demand-side and supply-side determinants of short-run growth and of the long-run trend rate
Costs and benefits	Weigh the impact on individuals, the economy and the environment; discuss sustainability
The economic cycle	Use real GDP, inflation, unemployment and investment to identify phases
Output gaps	Define positive and negative gaps
Causes of change	Explain global and domestic demand-side and supply-side shocks
Cyclical instability	Discuss credit and debt, asset price bubbles, destabilising speculation, animal spirits and herding

Short-run and long-run growth

Economic growth is an increase in real GDP: output measured at constant prices, so that rising prices do not count as growth.

Short-run growth is an increase in actual output. It usually comes from a rise in aggregate demand (AD) that uses spare capacity: idle workers and factories are put to work. Long-run growth is an increase in the productive capacity of the economy. The specification uses the term to mean the trend rate of growth of real national output over time.

PPC view. Put capital goods on the vertical axis and consumer goods on the horizontal axis.

Event	Where it shows on the PPC
Unemployment falls, spare capacity is used	Point moves from inside the curve towards the curve (short-run growth)
More or better factors of production	The whole curve shifts outward (long-run growth)
Output moves along the curve	Opportunity cost: gaining one good means giving up some of the other. This is not growth

AD/AS view. Short-run growth is a rightward shift of AD along an upward-sloping short-run aggregate supply (SRAS) curve, with real GDP rising and the price level rising too. Long-run growth shows as long-run aggregate supply (LRAS) moving right, which lifts potential output and, other things equal, leaves prices lower. A rise in LRAS is often shown together with SRAS shifting right.

Worked example: the trend rate. Country A’s real GDP rises from 640 to 780 over 8 years. The trend rate is the average annual compound rate g:

(780 / 640)^(1/8) - 1 = 1.2188^(0.125) - 1 = 0.0250 = 2.5% a year

Check: 640 × 1.025^8 is approximately 780. Use the compound method for a trend, not a simple average of yearly rates.

Determinants of growth

Demand-side determinants (short-run growth). Real GDP is demanded as consumption (C), investment (I), government spending (G) and net exports (X − M). Growth in any component raises AD.

• C rises with confidence, wealth, lower interest rates, tax cuts and easier credit.
• I rises with higher expected profits, lower interest rates and available finance.
• G rises with deliberate spending decisions.
• X − M rises with faster growth abroad, or a lower exchange rate that improves price competitiveness.

Worked example: contributions to growth. Country B’s real GDP is 500. Over a year, C rises by 8, I by 6, G by 2 and net exports fall by 1.

Change in AD = 8 + 6 + 2 - 1 = 15
Growth = 15 / 500 = 3.0%
Contributions (percentage points): C 1.6, I 1.2, G 0.4, net exports -0.2. Total 3.0

Demand-led growth only lasts while spare capacity remains.

Supply-side determinants (long-run trend). Anything that expands productive capacity: the quantity of labour (population, participation, migration), its quality (education, training, health), the capital stock (investment), technology, productivity, enterprise, natural resources, infrastructure and competition. The banking system matters because it channels savings into business investment funds.

Note the link: investment is on both sides. It raises AD immediately and raises capacity later.

Output gaps

• Positive output gap: real GDP is above the productive potential of the economy.
• Negative output gap: real GDP is below the economy’s productive potential.

Output gap (%) = (actual real GDP − potential real GDP) / potential real GDP × 100.

On AD/AS: a positive gap sits to the right of the LRAS curve (the economy is stretched, with shortages of labour and rising wage and price pressure). A negative gap sits to its left (spare capacity, higher unemployment, weak price pressure).

The economic cycle

Actual output fluctuates around the trend. A simple sketch:

real GDP
   |        peak            peak
   |       /\              /\        trend ----->
   |  ----/--\------/\----/--\------
   | recovery  \   /  \  /
   |            \_/    \/  trough
   +------------------------------- time

Common phases are the boom (growth strong, positive gap), the downturn or slowdown (growth falling), the recession (real GDP falling; a common convention is two consecutive quarters of decline) and the recovery (growth returns). Use several indicators together: real GDP growth, the inflation rate, unemployment and investment.

Worked example: reading the cycle in Country C. Potential output grows 2.5% a year from 500.

Year	Actual	Potential	Gap	Growth	Inflation	Unemployment	Investment growth
1	500	500.0	0.0%	n/a	2.1%	5.8%	n/a
2	520	512.5	+1.5%	+4.0%	2.9%	5.2%	+7%
3	541	525.3	+3.0%	+4.0%	3.8%	4.6%	+9%
4	553	538.4	+2.7%	+2.2%	3.1%	4.9%	+1%
5	538	551.9	-2.5%	-2.7%	1.6%	6.7%	-11%
6	551	565.7	-2.6%	+2.4%	1.2%	6.9%	+3%

Reading it: years 2 and 3 are expansion into a boom (strong growth, falling unemployment, rising inflation, investment up). Year 4 is a slowdown: output still grows but growth and investment slow, and the positive gap narrows. Year 5 is a recession: output falls, unemployment jumps, inflation eases, investment collapses. Year 6 is a recovery, but growth of 2.4% is below the trend of 2.5%, so the negative gap stays at -2.6%. Unemployment is a lagging indicator, so it still rises.

Causes of changes in the cycle: shocks

A shock is an unexpected event that shifts AD or aggregate supply.

	Global	Domestic
Demand-side	A fall in trading partners’ incomes cuts exports	A collapse in consumer confidence; sudden fiscal tightening
Supply-side	A rise in world commodity prices raises costs	A natural disaster destroys capacity; a new technology lifts productivity

Chain for a negative global demand shock: partners’ incomes fall, export orders fall, AD shifts left, real GDP falls and a negative gap opens, firms cut investment and jobs, and incomes fall again. The size depends on how open the economy is and how fast it can find new markets.

Chain for a negative supply shock: costs rise, SRAS shifts left, the price level rises and real GDP falls together (stagflation).

Cyclical instability

Cycles can be made larger by the behaviour of households, firms and banks.

1. Excessive growth in credit and debt. Cheap, easy lending lets spending run ahead of income. When interest rates rise or incomes disappoint, borrowers must cut spending.
2. Asset price bubbles. Prices rise beyond fundamental value because people expect further rises.
3. Destabilising speculation. Buying because prices are rising pushes prices up further, then selling in a panic pushes them down.
4. Animal spirits. Waves of optimism or pessimism, not calculation, drive spending and investment.
5. Herding. People copy others rather than judge for themselves.

Worked example: bubble and debt. House prices in Country D rise from 100 to 180, an increase of 80%. Households borrow heavily: debt rises from 90% to 130% of annual income.

Interest burden = debt/income x rate
At 2%: 0.90 x 2% = 1.8% of income  ->  1.30 x 2% = 2.6%
At 5%: 1.30 x 5% = 6.5% of income

Higher borrowing costs more than double the burden of the larger debt. Prices then fall to 110, a fall of 38.9% from the peak (110/180 − 1). A buyer who paid 180 with a 90% loan owes 162 on a house now worth 110: negative equity of 52. Households cut spending, banks cut lending and AD shifts left. Falls in asset prices can push the economy into recession.

Evaluation: the effect depends on the size of the debt, how it is spread, regulation of lending, and whether incomes keep rising.

Costs and benefits of growth

	Benefits	Costs
Individuals	Higher incomes, more jobs, more consumption and leisure options	Inequality may widen; longer hours and stress; some skills become obsolete
Economy	More tax revenue, lower unemployment, funds for public services and investment	Inflation and skill shortages if demand outpaces supply; more imports
Environment	Richer societies can fund cleaner technology	Resource depletion, pollution and climate damage

Per head. If real GDP grows 3.0% and population grows 1.2%, real GDP per head grows (1.03/1.012) − 1, about 1.8%. Growth that is shared widely means more to individuals than the total figure shows.

Sustainability. Growth is sustainable if it can continue without damaging the ability of future generations to meet their needs. Suppose Country E’s real GDP rises from 100 to 130 while emissions rise from 100 to 117.

Emissions per unit of output: 117 / 130 = 0.90 (down 10%)

Emissions are still 17% higher, so cleaner growth is not yet sustainable growth. Judging it depends on technology, carbon pricing and regulation, and whether the environmental stock can recover. Time matters: the costs often fall on later generations.

Common errors

• Calling any rise in output “long-run growth”. A move out of recession is short-run growth.
• Using nominal GDP when the question asks about growth.
• Showing a PPC shift for a recovery from a recession.
• Assuming a positive gap always means inflation. It makes pressure more likely.
• Listing costs and benefits without a judgement.
• Forgetting that investment affects both AD and productive capacity.

Official syllabus

AQA, AS and A-level Economics (7135 and 7136), specification version 1.3, 29 June 2022, section 3.2.3.1 on the AQA website (4.2.3.1 in the combined PDF).