For data tables that have two or more logical levels of row or column headers, use markup to associate data cells and header cells. If a table is used for layout, do not use any structural markup for the purpose of visual formatting. Provide summaries for tables. Provide abbreviations for header labels. Some people with cognitive or visual disabilities are unable to read moving text quickly enough or at all.
Screen readers are unable to read moving text.
Movement can cause such a distraction that the rest of the page becomes unreadable for people with cognitive disabilities. If you can't create a way for a user to freeze or control a moving element, or to turn it off, you should consider very carefully the inclusion of that moving element. Using style sheets with scripting to create movement allows users to turn off or override the effect more easily. Ensure that pages featuring new technologies transform gracefully. Ensure direct accessibility of embedded user interfaces.