Chart details Chart text

Overview

Text in a chart is just as important as graphical elements in helping users understand the chart and the data it shows.

Keep text concise and do not overload your chart with text. Too much text will make your chart cluttered and harder to read, especially on mobile devices. Make sure text is visible on mobile and desktop and not overlapping with other text or other chart elements.

Avoid duplicating text throughout your chart, except where necessary.

Your chart and chart text, and the text elsewhere in your bulletin or article, should work together to help your user understand the data. Use words or phrases in your chart that match the language used elsewhere in the release.

The exception to this is very long labels, which should be made more concise for charts. Use consistent language throughout your chart.

As with everything we publish, chart text should be in plain language, also known as plain English, and follow our content style guide (opens in a new tab) 

Chart titles

All charts must have a title that is:

• front-loaded
• in the active voice
• in sentence case
• as concise as possible
• 15 words or fewer

Read more about frontloading your content and writing in the active voice in our plain language guidance

The chart title should not spell out acronyms (opens in a new tab)  and quarters (opens in a new tab) 

Acronyms and quarters should be written out in the first instance in either the chart subtitle (opens in a new tab)  or chart footnotes (opens in a new tab) , even if they have been defined in the text in the same section as the chart.

Describe the trend

The chart title should describe the main trend you want the chart to show to the user.

Research shows that users are more likely to understand and remember the main trend from a chart where it is also in the chart title.

Your chart title does not have to refer to all the data shown in the chart. For example, a line chart could have a title describing a change in the last quarter, even if the chart itself shows several years’ worth of data.

Your chart may not be effective if the trend described in your chart title is not the most prominent visual trend in the chart. Consider changing the data you are choosing to present, or the chart type, to make the chart more effective.

Your chart title should complement but not repeat your section heading.

For bulletins, articles and methodologies, the title must always include a figure number, using the format “Figure X:” as shown in the following examples.

Figure numbers are generally not needed for digital content articles (opens in a new tab) 

Chart subtitles

Use the chart subtitle to provide a specific description of the data used in the chart. This must include the:

• statistical measure
• geographic coverage
• time-period

Follow this consistent order to help users find the information they need. Separate each description with a comma and write the time periods in full.

If any of these details are included in the chart title, do not repeat them in the subtitle.

Chart alternative text

Chart alternative text (alt text) is an accessible text description of a chart on a page.

Use chart alt text to provide a specific description of the type of chart and the main trend that it is showing.

A chart alt text sentence should be between 100 and 200 characters and always end with a full stop. Use the format “A [chart type] showing that [chart title].”

Do not abbreviate quarters in chart alt text. Always define the quarter, including the months covered, and the year. Read about how to write out quarters (opens in a new tab) 

Chart titles for interactive tools

Sometimes we produce interactive charts or tools that allow the user to explore the data themselves, or get personalised results.

For some interactive tools, it may not be possible or useful to provide a title that describes a trend. In this case, give the chart a title that prompts the user on how to use the tool and helps them make sense of the content.

Sources

Each chart must include the source of the data directly after the chart. This should be written in the following format:

[Name of publication or source of data] from [Name of organisation]

Read more about using multiple sources or data from other organisations in our citations, references and sources guidance (opens in a new tab) 

Footnotes

Footnotes should only be used to provide essential contextual information for a specific chart or table. They should be as clear and concise as possible.

Using too many footnotes can interrupt the flow of the publication. This is particularly the case on mobile devices, where text may wrap over several lines.

Avoid lengthy, detailed footnotes that require the user to scroll. Instead, provide a summary and direct users to more detailed information in the quality sections.

Footnotes should not be repeated across multiple charts. If important information applies to several charts, include it in the main text or quality sections.

Do not refer to or direct users to footnotes from another chart or footnote, or elsewhere in your publication.

Axis titles

We use axis titles to show the unit of measurement shown on an axis. Avoid duplicating other information from the chart title, subtitle or annotations in your axis title.

Keep axis titles as short as possible.

If your axis shows distinct categories or dates, you normally do not need an axis title.

Axis number labels

When displaying percentages or monetary values on a chart, always include the relevant symbols (% or currency symbols) directly in the axis labels. This helps users to understand and interpret the chart quickly.

If needed, you can also specify the unit in the axis title. For all other types of unit, include the unit only in the axis title and/or chart subtitle, not in the axis labels.

Dates in charts

For dates on a chart axis or in a legend, use the standard ONS date format “[Date] [Month] [Year]” depending on which information you need.

Years should be written as four digits. Months should be written out in full wherever possible. Where space is limited, you can use the shortened version of months (except for June and July).

You can also shorten quarters to Q1, Q2, Q3 and Q4 in chart text.

Use abbreviations consistently throughout your chart.

Always write out dates, months and quarters in full in chart metadata (for example, in chart titles or summaries).

Depending on the types of dates you are using on the axis, label either specific dates or date spans. For more information, see our guidance on Axes and gridlines (opens in a new tab) 

Category labels

Category names on a chart axis or in a legend should be clear and concise. Always shorten and simplify excessively long category labels. This makes your chart more accessible to users.

When using shorter labels, include any additional detail needed in the chart footnotes or surrounding text.

You can include long and short labels alongside each other in the data downloads.

Help improve this page

Let us know how we could improve this page, or share your user research findings. Discuss this page on GitHub (opens in a new tab)