# IELTS Task 1 Percentages: Accurate Comparisons | topin

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## Read the variable and unit before describing the change

A percentage usually expresses part of a defined whole. Before writing, name that whole: residents, spending, energy use or survey responses. Then inspect the categories and dates. A statement about the number of people is not automatically justified by a chart showing their percentage; the total population may have changed.

British Council's [data-description lesson](https://takeielts.britishcouncil.org/sites/default/files/2026-06/academic%5Fwriting%5Ftask%5F1%5Fdescribing%5Fdata%5Fand%5Fmaking%5Fapproximations.pdf) starts from axes and develops accurate descriptions and approximations. Our worked calculations are original examples of that principle. They are not extra official tasks or a requirement to compute relative changes in every report.

Imagine 20% of a town's residents cycle to work in 2010 and 30% in 2025\. You can say the proportion increased. You cannot calculate how many additional residents cycled without knowing the population totals. If the chart also supplies those totals, the count can be computed; if it does not, stay with the provided unit.

Create a tiny pre-writing note: subject, unit, dates and denominator. This takes less time than correcting an entire paragraph that treats thousands as individual people or percentages as absolute counts. For the broader reporting method, use the [Task 1 guide](/ielts/writing/task-1) and focus this article's practice on numerical precision.

## Distinguish percentage-point change from percentage change

Subtract two percentage values to obtain their difference in percentage points. From 20% to 30%, the difference is 30 minus 20, or ten points. For relative percentage change, divide that difference by the starting value: 10 divided by 20 is 0.5, or 50%. The denominator is what makes the calculations different.

From 40% to 50%, the difference is again ten points, but the relative increase is only 25%, because ten divided by forty is 0.25\. These two original examples show why writing “rose by 10%” can misrepresent the change. A clear endpoint sentence, “rose from 40% to 50%”, avoids the ambiguity.

When the starting value is zero, the ordinary relative-change formula divides by zero and is not usable. Describe the endpoints or the point difference instead. A report need not contain a relative-growth claim merely because another category has one. Choose the wording the data can support rather than forcing a formula everywhere.

If you are not certain about a derived calculation under time pressure, use accurate provided values and a direct comparison. “The share increased from a fifth to three tenths” is informative. An incorrect claim of doubling is worse than an ordinary endpoint description. Precision includes knowing when to avoid unnecessary arithmetic.

## Group an original budget table into meaningful contrasts

__Original budget shares; both yearly totals equal 100%__
| Category | 2010 | 2025 | Point change |
| -------- | ---- | ---- | ------------ |
| Rent     | 30%  | 40%  | +10          |
| Food     | 25%  | 20%  | −5           |
| Travel   | 20%  | 15%  | −5           |
| Leisure  | 10%  | 10%  | 0            |
| Other    | 15%  | 15%  | 0            |

Use the original household budget shares below. Rent rises from 30% to 40%, food declines from 25% to 20%, travel declines from 20% to 15%, leisure stays at 10%, and other spending remains at 15%. The stable rows matter because a summary claiming that every category except rent declined would be inaccurate.

As a final arithmetic check, add the category shares for each year. Both columns total 100%, so the categories form complete budgets in this invented example. This check would not automatically apply to a survey allowing multiple answers, where percentages may overlap. Read the chart’s definition before treating a total above 100% as an error.

The main summary is that rent took a larger share, while food and travel became smaller shares and the other two categories were stable. The biggest category remained rent. That overview selects the pattern; supporting sentences can compare the ten-point rent increase with the five-point reductions in food and travel.

A concise detail sentence is: “Rent's share rose by ten percentage points to 40%, whereas food and travel each fell by five points, reaching 20% and 15% respectively.” The word respectively connects values to categories in the same order. If you reverse the order of either list, the sentence becomes wrong even when every number came from the table.

Use the [overview-selection guide](/articles/ielts-task-1-overview-examples) to choose the main contrast before drafting. Do not mechanically describe all five rows in separate sentences. Grouping stable and changing categories lets the reader compare them, while preserving the exact units and endpoints.

## Use fractions and approximations only when they fit

Common proportions can make a report readable: 50% is half, 25% a quarter and 20% a fifth. For a value such as 48%, use just under half or approximately half if the level of precision suits the chart. If the exact value is available and matters to the comparison, retain it in the detail paragraph.

Avoid false precision when reading a graph. A line between labelled grid values may support “about 32%” rather than an exact decimal. Conversely, a printed table of 32.4% supports that number directly. Your wording should reflect the resolution of the supplied information; adding decimal places does not make an estimate more reliable.

Check the direction of approximate language. 52% is just over half, while 48% is just under half. Around half could describe either if the precise side is unimportant, but not if the question's main distinction is whether a majority is reached. Approximation should preserve the meaningful relationship.

For multiple pie charts, inspect what each whole represents. A category taking 40% of a smaller total can still be a smaller absolute amount than 30% of a larger total. If totals are not supplied, compare shares rather than asserting the category's actual quantity rose. This is a denominator check, not a demand to calculate every slice.

## Repair five common comparison errors

Incorrect: “Rent increased to 10%.” In our budget table, ten points is the change and 40% is the endpoint. Repair it as “Rent's share increased by ten percentage points to 40%.” By introduces a difference; to introduces the resulting value. Keep both labelled when they occur in one sentence.

Incorrect: “Food was twice lower than rent in 2025.” A clearer version is “Food accounted for half the share of rent in 2025”, because 20% is half of 40%. Another accurate version is “Rent's share was twice that of food.” Choose a straightforward ratio construction instead of an ambiguous comparative.

Incorrect: “The percentage of rent was 40 people.” The category and unit conflict. Repair it as “Rent represented 40% of household spending.” Incorrect: “Food and travel were 15% and 20%, respectively.” Reverse the values to match the listed order. Incorrect: “All non-rent categories declined.” Leisure and other spending did not decline, so qualify the statement.

Read the completed paragraph once with the table beside it, checking only numbers, subjects and units. Do a separate language check afterwards. Combining every editing goal into one quick scan makes numerical slips easier to miss. The [cohesion guide](/articles/ielts-writing-cohesion-referencing) can help ensure references such as that share still point to the correct category.

## Train accurate comparisons in short sets

Take one original or official table and write five sentences: largest category, smallest category, biggest change, stable category and one direct comparison. Then verify each against the values. This is a suggested exercise. You are practising accurate selection and language, not meeting a formal requirement to include exactly five kinds of sentence.

Next rewrite two sentences using a fraction or approximate phrase without changing meaning. If the revised version becomes less precise where the distinction matters, keep the numerical wording. Do not treat variety as a reason to replace an accurate term with an awkward synonym. In a report, consistent units and category names help readers.

Finally write a complete Task 1 response in the recommended allocation, with at least 150 words. Include a main-feature overview and organised support rather than a page of calculations. Keep derived arithmetic subordinate to the task: a reader should understand the visual more easily after reading your report.

[topin's free IELTS Academic mock](/ielts/practice-test), marked on the official scale, can test whether this accuracy holds in a complete session. Use official tasks and feedback as additional benchmarks. After marking, label each numerical error as wrong unit, wrong endpoint, wrong order or unsupported inference, then choose the next drill from the category that recurs.

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## FAQs

Is 20% to 30% an increase of 10%?

It is ten percentage points, or a 50% relative increase. Saying “from 20% to 30%” is often the simplest accurate description.

Do I need relative-change calculations in Task 1?

No. Use them only when helpful and accurate. Provided endpoints and direct comparisons are usually sufficient.

When should I use “by” and “to”?

Use by for the size of the change and to for the endpoint: rose by ten points to 40%.

Can I say “half” instead of 50%?

Yes where it accurately describes the same whole. For nearby values, use appropriate wording such as just under half.

Does a larger percentage mean a larger number?

Only if the denominators support that conclusion. Without totals, compare proportions rather than absolute counts.

## Sources (checked 5 October 2026)

* [British Council: describing data and approximations — checked 5 October 2026](https://takeielts.britishcouncil.org/sites/default/files/2026-06/academic%5Fwriting%5Ftask%5F1%5Fdescribing%5Fdata%5Fand%5Fmaking%5Fapproximations.pdf)
* [IELTS: Academic Writing specification — checked 5 October 2026](https://ielts.org/take-a-test/test-types/ielts-academic-test/ielts-academic-format-writing)
* [IELTS: public Writing band descriptors — checked 5 October 2026](https://ielts.org/cdn/Guides/ielts-writing-band-descriptors.pdf)

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