In an A-Level H2 Economics case study, a rate rising from 4% to 6% increases by 2 percentage points. Its relative increase is 50%, because the rise of 2 is half the starting rate of 4. Read the question to see which of those comparisons it asks you to make.
The 2027 H2 Economics (9570) syllabus gives Paper 1 two compulsory case studies, worth 30 marks each. The paper lasts 2 hours 30 minutes and contributes 40% of the qualification. Case study evidence can appear in text, figures or graphs. The worked examples below show how to name the right variable, use the right base and explain what changed.
- Subtract two rates to find a change in percentage points.
- Divide the difference by the starting value for a relative percentage change.
- Name the variable, period and direction in the answer.
Worked example | A slowdown with rising prices
In an invented economy, annual inflation falls from 6% in Year 1 to 3% in Year 2. The inflation rate fell by 3 percentage points, or by 50% relative to the Year 1 rate. Both rates are positive, so the price level still rose in Year 2 under these assumptions.
To see the difference, start a price index at 100. A 6% rise takes it to 106. A further 3% rise takes it to 109.18. The inflation rate went down while the price level kept going up.
An answer that says “prices fell by 3%” mixes up the direction of the rate with the direction of the price level. Write “inflation fell by 3 percentage points, from 6% to 3%, so prices were still rising but more slowly.”
| Variable | Earlier rate | Later rate | Percentage-point change |
|---|---|---|---|
| Inflation | 6% | 3% | −3 |
| Unemployment | 4% | 6% | +2 |
| Saving rate | 8% | 10% | +2 |
Choose the right base for a relative change
Suppose unemployment rises from 4% to 6%. Subtracting gives a rise of 2 percentage points. Dividing the difference by the starting rate gives 2 ÷ 4 × 100 = 50%. If the rate later falls from 6% to 4%, that is a fall of 2 percentage points but a relative fall of about 33.3%, because the base is now 6%.
Take care with a zero starting rate. A rise from 0% to 2% is a rise of 2 percentage points. The ordinary relative percentage-change formula divides by zero in this case and is undefined.
If the data are counts or dollar amounts, name the relevant unit. An increase in consumer spending from $100 million to $110 million is $10 million, or 10% relative to the starting amount. Percentage points would fit a comparison of two percentage rates or shares.
Use the data before explaining the cause
When the task asks for a description, report the direction and size of the change using the given period. If the task asks for an explanation, apply a relevant economic mechanism to the case and use the extract to support it.
Suppose an extract says energy costs eased while inflation fell. You could explain how lower energy costs reduce cost pressures for firms that use energy intensively. The co-movement alone cannot establish how much of the inflation change came from energy. Look for the composition of the index and what happened to other prices before making that judgement.
If the question asks for a comparison across economies, check that the indicators use compatible definitions and periods. A month-on-month rate and a year-on-year rate describe different changes even if both are shown as percentages.
Three short calculations to rehearse
A saving rate rises from 8% to 10%. The rise is 2 percentage points and 25% relative to the starting rate. State which answer the question asks for.
A share of households with internet access rises from 80% to 88%. The gain is 8 percentage points, or a 10% relative rise in the share. If asked about the number of households, you also need the household totals for the periods concerned.
Annual real GDP growth falls from 4% to 2%. Growth slows by 2 percentage points. Real GDP still rises in the second year under the example’s assumptions. A parent or study partner can check your response by asking which measure fell and which measure kept rising.
Frequently asked questions
Can I write “percentage points” as “pp”?
Use the full phrase when you have room so the unit is unambiguous.
What if the task only says to compare the rates?
Name both rates and their direction, then express the difference in percentage points if you quantify the gap.
Does the same arithmetic apply outside Economics?
Yes. It applies to any comparison of rates or shares expressed as percentages. The interpretation depends on what the rate measures.
Official information
SEAB’s 2027 A-Level H2 Economics syllabus (9570), Scheme of Assessment and Description of Components for Paper 1. Checked 8 November 2026.