Fat, Jim is basically correct, altho the "High Score" is an average of several scores.
USPSA has various stages that are called a "classifier," as the specifics of the stage (target distance, etc) are spelled out. The gun club putting on the match measures out the distance so that, in theory, the club shooting Classifier 99-11 (El Presidente) in Tennessee is identical to the same stage set up in Florida, Texas, etc.
Scores are already on file for the classifier stages and your score is compared to it.
To shoot 100% of this one, in Limited division, you need to shoot 60 points in 5.55 seconds. The Hit Factor is 10.81, so you can drop some points if you shoot it faster.
94.9% is 60 points in 5.85 seconds, so a mere 3/10ths of a second makes a difference between being a Grandmaster or just a high Master.
The USPSA Hit Factors are not public, but this one has been out there for literally decades.
Initially, USPSA takes your first 4 classifers to get you classified. (if you find a "super classifier match, you can be classified in ONE day.) After that, they take your high 6 scores of your most recent 8 and averages them. If your average is 95% or better, then you're a Grand Master. As you can see, you cannot luck your way into GM status.
Check out
www.uspsa.com for more info.