The mistake that costs Task Achievement
Most pie chart questions give you two pies — two years, two countries, two age groups. And the moment there are two, candidates start describing change:
"Spending on food fell from 40% to 30%, so households spent less on food in 2020."
The first half of that sentence is fine. The second half may be false. If total household spending doubled over the period, then 30% of the 2020 total is more money than 40% of the 2010 total — food spending rose, even though its share dropped.
This is not a vocabulary slip. It is a claim about the data that the data does not support, and it lands on Task Achievement.
| Do not write | Write |
|---|---|
| Households spent less on food. | Food accounted for a smaller share of spending. |
| The number of people using buses fell. | Buses made up a smaller proportion of journeys. |
| Coal use dropped by 15%. | Coal's share of the energy mix dropped by 15 percentage points. |
The one exception: if the chart or the caption states the totals (total spending: £2,000 in 2010, £2,400 in 2020), then you can talk about amounts — and you should, because working out that a shrinking share still meant more money is exactly the insight a high-band answer contains.
The language of proportion
Nearly every low-scoring pie chart answer is built from one structure — X was 35%. Y was 20%. — repeated until the slices run out. There are four ways to say a proportion, and using them is most of the Lexical Resource mark on this task.
1. Verbs of composition
- Housing accounted for 35% of total expenditure.
- Transport made up just under a fifth of the budget.
- Food and rent together represented more than half of all spending.
- The remaining three categories comprised the final 12%.
2. Fractions, which sound better than percentages
A strong answer rarely says 25% twice. It says a quarter, and it does so because rounding to a fraction is what a human summarising a chart would naturally do.
- around a quarter (24–26%) · roughly a third (32–35%) · just under a half (45–49%)
- a fifth (20%) · two-thirds (66%) · the vast majority (over 75%) · a small minority (under 10%)
3. Approximators, so you are never wrong
Approximately, roughly, just over, just under, slightly more than, nearly. Reading a slice as exactly 27% when it is 26% is a factual error; roughly a quarter cannot be.
4. Ranking, which is the point of the chart
- The largest share by far went to housing.
- Transport ranked second, at 22%.
- Education received the smallest allocation of the six.
How to organise it (and not list the slices)
A pie has few enough slices that reading them all out feels possible. Resist it — a list still scores as a list, and the coherence mark comes from grouping and ranking, not from completeness.
- Paraphrase the title in one sentence.
- Overview: which slice dominates, which is negligible, and — if there are two pies — what changed in the shares. No figures.
- Body 1: the big slices. The one or two that carry most of the pie, with figures.
- Body 2: the small ones, grouped. The remaining four categories each accounted for less than 10%.
With two pies, organise by theme rather than by chart. A paragraph on the 2010 pie followed by a paragraph on the 2020 pie forces the reader to compare them for you, and comparing is the task.
| Weaker organisation | Stronger organisation |
|---|---|
| Para 1: everything about 2010. Para 2: everything about 2020. | Para 1: the categories whose share grew. Para 2: the categories whose share fell or held steady. |
Overall, housing dominated the budget in both years, while the shares taken by food and clothing both contracted noticeably. — that is an overview of two pies in one sentence, and it commits to nothing the chart does not show.
Before you submit
- Have I said share/proportion, and avoided claiming that an amount rose or fell?
- Have I used percentage points for a change in share?
- Is there an overview with no figures in it?
- Have I grouped the small slices rather than listing them?
- If there are two pies, is my organisation by theme, not by chart?
- Have I resisted explaining why anything changed? (Task 1 does not ask, and it earns nothing.)
Frequently asked questions
Can I say a figure 'increased' in a pie chart?
Say the share increased, not the amount. A pie chart shows how a whole was divided, not how big the whole was — so if food fell from 40% to 30% of spending, you know its share shrank, but you do not know whether households spent less on food, because the total may have grown. Claiming the amount fell is a factual error about the data and it costs you on Task Achievement.
What is the difference between percent and percentage points?
A share moving from 40% to 30% has fallen by 10 percentage points. It has not fallen by 10% — a 10% fall would take it to 36%. Using 'percentage points' for a change in share is a small, cheap signal of precision, and examiners notice the distinction.
What verbs should I use for a pie chart?
Verbs of composition: accounted for, made up, represented, comprised. 'Housing accounted for 35% of expenditure' is doing what the chart does; 'housing was 35%' is not really a sentence about anything. Combine them with fractions — 'roughly a third' reads far better than repeating 34% — and with approximators, so that a slightly misread slice never becomes a factual error.
How should I organise an answer with two pie charts?
By theme, not by chart. One paragraph on the categories whose share grew and one on those that fell or held steady makes the comparison for the reader; a paragraph on each year leaves them to do it themselves, and comparing is the task. The overview should say what dominated in both charts and what shifted between them.
Do I have to describe every slice of the pie?
No, and describing them all in turn produces a list, which scores poorly on coherence however accurate it is. Give the large slices individually with figures, then group the small ones — 'the remaining four categories each accounted for less than 10%' handles them in a single sentence and reads as an organised answer.