Take the difference between the ratings and add or subtract the result to the time posted at the other track. It will show what the time might have been if the race had been at the track where the horse is on the present night. Changes in form can be spotted by comparing race lines week to week. Sometimes, though, what appears to be a downward swing in form may not be that at all. Horses must also race frequently to keep their form, and they compete on an average of every six to ten days.
Long layoffs are almost always a bad sign.