It determines how you must alter your timing for safe jumping character after knocking them down based on how quickly they go from knocked down (invincible) to fully standing (vulnerable). However when you safe jump, or cross someone up, you must also take into account the vertical and horizontal lengths of their character’s hitbox. Overall it’s a neat piece of information. But learning how to safe jump, approach someone for a meaty, or really approach a knocked down opponent for okizeme in general, is something that I’d recommend getting a feel for rather than trying to learn anything from the raw data. It’s still neat information though. Here’s the original from T.Akiba’s site.
An example of something you’ve done that is way easier to use than trying to feel it out is the throw range chart. Trying to feel who has a larger throw range in ST would take forever. The chart is quite helpful and I reference and use it all of the time.