A pie chart shows that trains received 31% of a transport budget while roads received 52%. Which sentence is accurate?
Roads received 21% more funding than trains.
That sentence confuses percent with percentage points. The visible gap is 21 percentage points. Relative to the train share, the road share is about 68% higher, but that calculation is rarely the clearest description. A safer sentence is:
Roads accounted for 52% of the budget, 21 percentage points more than trains.
IELTS Academic Writing Task 1 can present one or more graphs, charts, or tables. IELTS asks you to summarize the information by selecting and reporting the main features and making relevant comparisons. The response must contain at least 150 words, and the official guidance recommends about 20 minutes. All required information is in the visual, so your job is description, not explanation from outside knowledge.
This lesson focuses on the lexical decisions created by bar and pie charts: naming a share, identifying a ranking, measuring a gap, and describing composition without implying causes. Continue with the IELTS vocabulary practice hub or explore the Exam English hub.
Read the unit before choosing the verb
A bar can represent people, tonnes, dollars, hours, or percentages. A pie chart normally divides a whole into shares. Before writing, label three things:
- the measured unit;
- the categories being compared;
- whether the visual shows one time, several times, or no time dimension.
Then choose two or three main features. An overview might identify the largest and smallest shares and a broad contrast. Detail paragraphs can support that overview with selected figures. Do not narrate every bar or slice.
1. Account for: state a share of the total
Account for can mean form a stated portion of a whole.
Public transport accounted for 10% of total spending.
Use category + accounted for + share. The category forms that part of the total. In another common sense, account for means explain a result, but a chart does not supply that explanation merely by displaying a percentage.
The two smallest categories together accounted for 4%.
That sentence is valid if the two visible shares total 4%. Avoid accounted 10%; the verb requires for. Also avoid writing that a category “accounted for the increase” unless the visual actually establishes an explanation, which it usually does not.
2. Constitute: let the part form the whole
Constitute can say that one or more parts form a total or share.
Rail and public transport together constituted 41% of the budget.
The parts are the subject. This direction matters. The budget constituted rail and public transport reverses the relationship. Make up is a natural alternative; constitute is useful when its formal register fits the neutral academic description.
Do not use the word as decoration. It does not mean receive, increase, or rank. It simply describes composition.
3. Comprise: put the whole before its parts
Comprise normally uses the opposite direction in the clearest taught pattern:
The final category comprised three services: buses, ferries, and local rail.
The whole is the subject and the parts follow, with no of. Avoid comprised of if you want the least disputed form, and do not write comprises of. For most statistical charts, account for or constitute will be more direct because the task often asks about shares rather than a named whole followed by a list of parts.
Use comprise only where the visual genuinely groups components. It says nothing about their relative importance.
4. Predominant: the largest or main category
Predominant means the most important, noticeable, or common element in a stated set.
Road spending was the predominant category, at 52%.
The ranking evidence earns the word: 52% is higher than every other category. Do not use predominant merely because a category is common or visually noticeable. Prevalent means widespread and usually describes occurrence across a population or setting; it does not identify the largest slice.
If two categories are close, a plain comparison is often better:
Road spending was the largest category, followed by rail.
The simplest accurate wording is stronger than an advanced adjective unsupported by the data.
Understanding is only the first step.
Lyra Practice helps you retrieve and use high-value workplace expressions in realistic situations until they feel natural.
Start a practice session →5. Disproportionate: use only with a stated benchmark
Disproportionate describes something too large or too small in relation to a relevant comparison. One charted percentage alone cannot establish it.
Suppose one bar chart shows that a group forms 20% of users and another shows that it receives 45% of support. You may write:
The group received a disproportionately large share of support relative to its share of users.
The benchmark is explicit. By contrast, “roads received a disproportionate 52%” is an interpretation unless the visual supplies an expected or comparative baseline. Task 1 does not ask whether the distribution is fair.
6. Largely: qualify a composition claim
Largely means mainly or for the most part, not completely.
The budget was largely allocated to roads and rail, which together represented 83% of spending.
The figure supports “for the most part.” Do not use largely to mean greatly: “the share rose largely” is not the normal way to describe a large increase. Write rose substantially if the numerical change supports that description.
Because largely leaves a remainder, the sentence should not later claim that the named categories made up the entire total.
7. Negligible: a contextual judgment, not merely small
Negligible means too small to matter for the current decision or analysis.
The difference between the two smallest categories was one percentage point.
The number establishes a very small gap, but it does not establish that the gap is unimportant. Negligible is not an automatic replacement for small or marginal. A one-point gap may decide a close ranking. Because a descriptive chart usually provides no decision criterion for materiality, report the number or use a size word instead:
The categories differed by one percentage point.
Percentage, percentage point, fraction, or raw value?
Keep these forms separate:
- A rise from 20% to 30% is 10 percentage points.
- Relative to 20%, that is a 50% increase.
- 25% is one quarter; 50% is one half.
- A bar labelled 25,000 people is a raw value, not 25%, unless the axis says so.
Approximate fractions are useful only when they remain faithful: just over a third for 35%, roughly a quarter for 24%, and nearly half for 48%. Do not turn 39% into “almost half.”
Worked bar-and-pie response
Imagine a bar chart showing visits to four venues: museum 80,000, gallery 65,000, theatre 45,000, and archive 10,000. A pie chart shows funding shares of 40%, 30%, 25%, and 5% respectively.
Overview:
Overall, the museum ranked first for both attendance and funding, whereas the archive had the lowest values. The two leading venues accounted for 70% of funding and attracted the majority of visits.
Selected detail:
Museum attendance stood at 80,000, 15,000 above the gallery figure. The museum also received the predominant funding share, at 40%, while the gallery accounted for 30%. The theatre’s 45,000 visits represented more than four times the archive total, although its funding share was five times as large. Together, the museum and gallery constituted 70% of the budget.
Notice what the response does not claim. It does not say funding caused attendance. It does not call the archive’s share unfair. The two visuals allow comparison, not causal explanation.
Controlled practice
1. Repair the unit
The share rises from 35% to 50%.
Incorrect: It rose by 15%.
Answer: It rose by 15 percentage points. If you calculate relative change, it rose by about 43%, but name that calculation clearly.
2. Choose the direction
Complete the sentence: “The three smaller categories ___ 48% of the total.”
Answer: constituted or accounted for. Comprised in a parts-first construction is attested but disputed; these alternatives avoid the issue.
3. Reject an unsupported evaluation
Parking received a disproportionate 30% of funding.
Repair: Parking accounted for 30% of funding. Use disproportionate only when another visible measure supplies a meaningful benchmark.
4. Build an overview
Write two sentences for a pie chart with shares of 45%, 32%, 18%, and 5%.
A controlled answer is:
Overall, category A was predominant, while category D accounted for the smallest share, at 5%. The two largest categories together constituted 77% of the total.
The chart supports smallest and the exact figure. It does not supply a practical criterion showing that 5% is too small to matter, so negligible would add an unsupported evaluation.
A final checklist
Before submitting, ask:
- Did I state the unit accurately?
- Did I distinguish percentages from percentage-point gaps?
- Does the overview identify major rankings or composition?
- Did I support predominant with a ranking and disproportionate with a benchmark—and avoid negligible unless the task supplies a genuine importance criterion?
- Did I select details rather than list every value?
- Did I avoid explaining why a pattern exists?
If you want to practise retrieving precise vocabulary for chart comparisons, try Lyra Practice.
Sources
- IELTS Academic Writing test format
- IELTS Academic Writing sample tasks
- IELTS Writing test preparation resources
Related
- IELTS Vocabulary for Change and Trends
- IELTS Task 1 Table Vocabulary
- PTE Describe Image Vocabulary for Trends
- PTE Describe Image Vocabulary for Maps, Processes, and Photos
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