When trying to show information in a table, never use color as its only indicator. Some users may not be able to see color. Others may not be able to tell colors apart. The best way to show information is to have multiple indicators. One of them can be color, but the other should be text, either normal text or alt text.
This table only uses color to convey meaning. This table would be considered inaccessible because some readers may not be able to distinguish the colors and their meaning.
This table uses color and text to convey meaning. It is accessible now because there is a second indicator to what the information is telling a reader.
Section 3.2: Creating a Text Description
Move the location of your chart or graph to a new location next to cell A1.
Click cell A1 and type in a brief description of the details in your chart. Then click the Wrap Text button to contain the description to cell A1. This will allow screen readers to explain the details of the charts to the readers and will make it easier for students with disabilities to understand the data.
While this image does contain a description, it does not explain everything in the graph. It fails to mention the data within the table. Anything in the table or graph or chart must be covered in the long description.
Section 3.3: Color Contrast
Open a blank sheet in Excel.
When typing in text you want to consider the color contrast between the text and the background. For small text (under size 18), a good contrast ratio to aim for is 4.5:1 or higher. For bigger text (over size 18) a good contrast ratio is 3:1 or higher. Black text on a white background or 21:1 is considered to be the most accessible contrast ratio.
As you can see in the example, good color contrast makes the text easier to read for the viewer.
Section 3.4: Adding Visual Queues
When using color to convey information, always be sure to add an extra visual queue. For many readers, color is hard to see, so they need another way to read the data.
To add an additional queue, click the chart. Click the Plus shaped button and add Data Labels.
Section 3.5: Using Cell Styles
Excel Cell Styles allow you to apply formatting styles to your workbook or table. Some of the formats include number type, alignment, headings, font, borders, fill, text, etc. These styles provide a very fast way to format your workbook to more accessible and easier to read. Follow these rules when using cell styles.
When using styles, like the Bad, Good, and Neutral format, be sure they have a strong color contrast ratio between the text and the background. 4.5 : 1 or higher is best.
Always follow the rules of the hierarchy. The Title style is used on titles, the Heading Style is used on Headings. Heading 1 should be used on your main heading, and Heading 2s are always children of Heading 1s.