When task requirements dictate that current information changes be continuously viewed and the display is changing so rapidly that the information is difficult to read, the user should have the capability of simultaneously viewing the information in a supplemental 'snapshot' display (i.e., a display frozen to enhance readability) along with the continuous display.
Additional Information:
For example, if a numeric data display is changing rapidly and the user finds it difficult to read, it should be possible to display a frozen, unchanging value representing the data at the point of the request. The original display should continue to be presented.