The exercise rating was a measurement of how successful a battle simulation was.

In 2266, Spock reported that the exercise rating for a simulation the USS Enterprise was running was 94%. Captain James T. Kirk suggested they try for 100%, to which Spock agreed. Leonard McCoy asked what Kirk would do with the 6% when they got it, but Kirk's reply was interrupted by Yeoman Janice Rand's entry with the captain's dietary salad. (TOS: "The Corbomite Maneuver")