7. Illustrations, Charts, and Text Boxes

Content: Chart Generation, Names, Alt Text, Description, Text Graphics, Contrast, Animated Graphics.

7.1 Chart Generation

A chart is generated in Excel on the basis of a table of data.

Further information

What does this mean?
Excel is a program designed for processing and presenting data. This includes creating charts based on data. Charts should therefore not be copied into Excel as images, but created directly within Excel.

Why is this important?
It is important to generate charts in Excel on the basis of table data because they contain more information than simple image copies. People with visual impairments who rely on screen readers cannot access visual information directly, so an alternative form of presentation is necessary. Although alt text is limited to a maximum of 125 characters and cannot include every detail, it should establish a link to the underlying table. Screen readers can read out the information from the table, making the data accessible to people with visual impairments.

How can you implement/check this?
To create a chart from a table in Excel, you can follow these steps:

1. Make sure that your data in the Excel table is accurate and complete, with clearly labelled columns and rows.
2. Select the range that you want to display in the chart, including the relevant columns and rows.
3. Go to the Insert tab in Excel.
4. Select the chart type that best suits your data. Excel offers various chart types such as column, line, pie, and bar charts.
5. Adjust the chart as needed by adding axis labels, titles, legends, and other formatting options to make it clear and meaningful.
6. Position the chart where you want it on your worksheet.

 

7.2 Names

Illustrations, charts, and text boxes have meaningful names.

Further information

What does this mean?
Illustrations, charts, and text boxes are given clear and precise names that indicate the content or function of the respective element.

Why is this important?
Assigning meaningful names in documents and Excel is very important because it enables users, including those with visual impairments, to navigate and interpret content efficiently. Clearly named objects such as illustrations, charts, and text boxes allow screen readers to reproduce the content more accurately, giving students better orientation and a deeper understanding of the data. This improves the overall clarity and comprehensibility of documents and makes it easier for all users to understand and process the information effectively.

How can you implement/check this?
To ensure that meaningful names are used for illustrations, charts, and text boxes in an Excel document, you can follow these steps:

1. Open the Selection Pane in Excel.
2. Use the search function in the Selection Pane to locate all illustrations, charts, and text boxes on the worksheet.
3. Make sure that all objects are listed so that they can be checked systematically.
4. For each object in the list, enter a clear and concise name that describes its content or function.
5. Once all names have been assigned, close the window to apply the changes and save the named objects.

7.3 Alt Text

Illustrations, charts, and groups of graphic elements that convey content have a short, concise alt text. The alt text for charts refers to the corresponding table by its table name, includes the chart type, and provides information about the content. Illustrations and groups with no meaningful content are marked as decorative.

Further information

What does this mean?
To improve the accessibility of an Excel file, all illustrations, charts, and groups of graphic elements it contains should be provided with alt text that describes them. Alt text is a short and concise description of the content of a graphic that is read by screen readers and text-to-speech software to help users understand the content.

Purely decorative illustrations, charts, and groups of graphic elements with no relevance to the content should be marked accordingly. In Excel, these elements can be marked as decorative to indicate that they contain no relevant content and can therefore be skipped by screen readers.

Charts in Excel are generated from data tables. To establish the connection between a chart and its table, the alt text should include the table name. In addition, the alt text should specify the chart type and the content of the chart.

Why is this important?
Appropriate alt text for an image is important because it enables all users to understand the content of that image. If an image has no alt text, or if the alt text is inadequate, the image becomes inaccessible to users of screen readers and text-to-speech software. This means that these users may miss important information contained in the image.

Appropriate alt text, for example, describes an illustration briefly and concisely and explains how it relates to the content of the file or a table. If the illustration contains important information that is not, or cannot be, presented elsewhere in the text, it is important to include this information in the alt text so that it can be conveyed by screen readers and text-to-speech software. A detailed description of the illustration is not usually necessary in alt text. If an illustration, chart, or group of graphic elements contains a great deal of important information, this should either be included in the main text itself or provided in a longer text alternative. As a general rule, alt text should not exceed 120 characters.

The alt text for an Excel chart showing revenue trends might read: Quarterly revenue trends – column chart. Table 'Annual Revenue' 2021–2023. This clearly communicates what the chart shows, what type of chart it is, and which table it refers to. Screen reader users can therefore access the relevant information about the company’s revenue trends even without seeing the chart.

How can you implement/check this?
To add alt text to an image in Excel, left-click the image and select Alt Text from the Picture Format menu. Then enter a precise description of the image content in the text box. If the image is purely decorative, mark it as such and leave the alt text field empty. To mark an image as decorative, proceed as follows:

1. Select the image that you want to mark as decorative.
2. Right-click the image and select Format Picture from the drop-down menu if you are using Windows. On a Mac, you can alternatively select View Alt Text, which opens a pane on the right-hand side.
3. In the Picture Format tab, select Alt Text.
4. In the Alt Text dialogue box on Windows, tick the checkbox Mark as decorative. On a Mac, select the Mark as decorative option below the text field.
5. Click OK to save the changes.

Excel also offers a built-in feature that allows you to check whether alt text has been provided for a graphic. You can also check for redundant alt text by reading the surrounding text and ensuring that it does not repeat the same information.

To use Excel’s built-in feature to check whether alt text exists for illustrations, charts, or graphic groups, proceed as follows:

1. Select the image for which you want to check the alt text.
2. Right-click the image and select Format Picture from the drop-down menu. On a Mac, you can alternatively select View Alt Text, which opens a pane on the right-hand side.
3. In the Picture Format tab, select Alt Text.
4. Check whether the alt text field has been completed. If it has, the image contains alt text. If not, the alt text is missing and should be added.

Although Excel can generate alt text automatically on request, this auto-generated text is often not suitable and should therefore be reviewed and, if necessary, revised.

7.4 Description

Content-rich, that is, complex illustrations, charts, and groups of graphic elements are described specifically within the document, for example as a table, alt text, other text, or a link to a website, including the data they contain where appropriate.

Further information

What does this mean?
A detailed descriptive text alternative for a content-rich, complex illustration, chart, or group of graphic elements contains a fuller description of the content and its significance for the file or table. Unlike alt text, which only provides a brief summary of the image content, a detailed text alternative should convey all important details necessary for understanding the illustration or chart. It should use clear and precise language and include all important information shown in the illustration, including colours, shapes, text, people, places, and actions where relevant. However, the description should not be redundant or unnecessarily long and should be limited to the relevant information contained in the illustration. Data-based charts in particular should be described in detail in order to explain the relationships they present.

If a text alternative is required for a visual representation, it should be provided either in the same file or in a separate document. The text alternative should be included in the same file as the illustration or chart and placed near it. This makes it easier for users who need an image description to find it. If the text alternative is provided in a separate document, the main document should refer to it, for example via a link, so that it can be accessed easily.

Why is this important?
Using detailed descriptive text alternatives is an important aspect of digital accessibility because it ensures that users with visual impairments can understand the content of complex illustrations and charts. A detailed descriptive text alternative can be particularly important if the illustration contains key information that cannot be conveyed elsewhere in the text of the file. Since complex illustrations are often difficult to describe, it is especially important that they are accompanied by a precise and detailed text alternative so that everyone can understand the content of the illustration or chart.

An example of a detailed descriptive text alternative for a complex illustration might be: The image shows a group of people sitting around a round table and having a discussion. In the middle of the table is a cake with 'Happy Birthday' written on it. The people are standing around the table, smiling and raising their glasses in a birthday toast. The room is decorated with balloons and bunting, and a band can be seen playing music in the background. The more important the details are for understanding the content, the more thoroughly they must be described.

How can you implement/check this?
A descriptive text alternative should contain a precise and accurate description of the visual element, for example an image, chart, or graphic, and convey its significance for the content of the file. The following steps may help you create a good descriptive text alternative:

1. Identify the visual element: consider which visual element is to be described and what information it contains.
2. Describe the visual element: describe it in as much detail as necessary to create a clear understanding of what is shown.
3. Consider the context: think about how the visual element fits into the context of the file and what information it conveys. Make sure the text alternative helps the reader understand its significance within the Excel file.
4. Use clear and concise language and adapt it to the target audience where necessary.
5. Avoid redundancy: do not repeat information that is already included in the main text of the file.

You can check your text alternatives by following these steps:

1. Check whether the text alternative includes all key information from the visual element.
2. Ensure that the text alternative is understandable and easy to read.
3. Check whether the text alternative makes sense in the context of the file and has a clear connection to the text or other visual elements.
4. Ask someone who is unfamiliar with the information conveyed by the visual element to read the text alternative and assess whether they can understand its meaning and purpose.
5. Check that the text alternative is not redundant, that is, that it does not repeat information already presented in the text.

7.5 Text Graphics

Illustrations are not used to represent text (text graphics). Exception: essential text graphics have meaningful alt text. Redundant text graphics are marked as decorative.

Further information

What does this mean?
It is recommended not to present text by means of text graphics. Instead, text should be typed and formatted as actual text. If text graphics are used nonetheless, it is necessary to provide alt text that describes the content of the graphic. If the text graphics are redundant and contain the same text as the surrounding text, they should be marked as decorative.

Text graphics are graphics consisting entirely of text characters and symbols and containing no images, photographs, or other visual elements. They are frequently used in the design of logos, posters, banners, and other marketing materials. WordArt is a type of text graphic that allows users to style text in various forms.

Why is this important?
The use of text graphics can create accessibility barriers in digital content because they may not be recognised properly by screen readers or text-to-speech software used by people with visual impairments. If text is entered and formatted as real text, it can be read more easily by assistive technologies. However, if text graphics are used, it is important to provide alt text to ensure that the content of the graphic can be understood by all users.

How can you implement/check this?
To avoid text graphics in Excel, enter and format text as actual text rather than inserting it as an illustration. If you do use text graphics, you can provide alt text by right-clicking the illustration and selecting Alt Text. In the Description field, enter a description of the text shown in the illustration.

If the text graphics are redundant, you can mark them as decorative by right-clicking the graphic and selecting Mark as decorative.

7.6 Contrast

Graphic elements that convey information, for example lines or adjacent areas, have a minimum contrast ratio of 3:1 against the background.

Further information

What does this mean?
Graphic elements that convey information are visual elements that communicate information within a document. These include, for example, lines, adjacent areas, and other graphic aids. When used in Excel, they must have a minimum contrast ratio of 3:1 against the background of the document. This minimum contrast refers to the difference in brightness or colour between the graphic elements and the background.

Why is this important?
For users with visual impairments, sufficient contrast between graphic elements and the background can be crucial in enabling them to recognise those elements. Insufficient contrast makes elements harder to perceive and can lead to misinterpretations. It is therefore important that graphic elements such as images or buttons have sufficient contrast.

Adequate contrast not only helps users with visual impairments. Users who work in poor lighting conditions, use black-and-white printouts, or follow a presentation via a projector also benefit from a high contrast ratio. Sufficient contrast ensures that content is clearly visible and therefore easier to understand and process.

How can you implement/check this?
In Excel, there are various ways to achieve a minimum contrast ratio of 3:1:

1. Use high-contrast colours: choose colours that contrast strongly with each other, for example black on white or yellow on black.
2. Use built-in colour schemes: Excel offers a variety of built-in colour schemes designed to support readability and contrast. You can find these options under Page Layout and then Colours.
3. Check the contrast using an online tool: various online tools can calculate the contrast between two colours and show whether the minimum ratio of 3:1 is met.

However, it is important to note that a contrast ratio of 3:1 is only the absolute minimum. A higher contrast ratio is recommended, especially if the document is intended for readers with visual impairments or reading difficulties.

To ensure that the contrast ratio between information-carrying graphic elements and the background is optimal, you can use free online tools or downloadable software.

7.7 Animated Graphics

No animated graphics, such as GIFs, are used.

Further information

What does this mean?
Animated graphics in the form of GIF files should not be used in an Excel file. Animated graphics, or GIFs (Graphics Interchange Format), are graphic file formats that can play a sequence of images in a loop to create a short animation. Because of this looping function, GIFs continue to play until the user closes them or scrolls on. Still images can also be converted into GIF format, but this significantly reduces image quality.

Why is this important?
Animated graphics should not be used in accessible digital content. It is important to note that GIFs generally do not offer a way to pause or stop the animation, which can make it difficult for users with, for example, concentration difficulties to absorb the content or focus on content outside the animation. In addition, rapid movement or flickering effects can trigger seizures in some users with photosensitivity.

How can you implement/check this?
You can use static graphics instead of animated GIFs to convey information. Depending on the operating system, checking for GIFs works slightly differently:

Mac

1. Check whether the Excel file contains any animated graphics.
2. If so, consider whether these graphics add value to the content of the Excel file.
3. If the animated graphics do not add value, remove them from the document.
4. If you want to keep the graphic, switch off the animation.
5. Right-click the animated graphic.
6. Select the Cut option.
7. Click Home in the menu bar at the top.
8. Click the arrow next to the Paste button.
9. Select the Paste as Picture option.
10. The image should now no longer be animated.

Windows

1. Review all graphics in the Excel file and pay particular attention to those that move.
2. Check whether the moving graphics add value to the content of the Excel file. If not, remove them.
3. If you want to keep the graphic as a static image, right-click it.
4. Select the Cut option from the context menu.
5. Right-click again where you want to reinsert the image.
6. Select Paste and then Picture from the menu.
7. The image should now be inserted as a static graphic without animation.