What Is “Course Rating?”
The quick answer is that it’s a single number indicating the difficulty of a golf course to an expert golfer, a “par golfer”. The figure is used when calculating handicaps.
The Course Rating is a number, close to par for the course, and is expressed with a single decimal digit. For example: If par for a course is 72, its Course Rating might be 71.4.
Rating values go up with difficulty.
Actually, for any given golf course, you can expect to see three (or even more) values for the Course Rating. Each value corresponds to a different tee.
For example: On this same course, the Course Rating for golfers who play from the men’s blue tees might be 72.8. From the men’s white tees, the Course Rating might be 71.0. The ladies’ red tees may be rated at 73.3.
These figures are almost always printed on the score card.
What is “Course Slope”?
The quick (and overly simplistic) answer is that it’s a single number indicating the difficulty of a golf course to a “bogey golfer”. The figure is used when calculating handicaps.
The Course Slope value is a two- or three-digit integer, always between 55 and 155, with 113 being the average or “standard” value.
Slope values increase with difficulty. But there is a catch that we’ll discuss shortly.
There will be one Course Slope for each Course Rating. The blue men’s tees might have a Course Slope of 123. The white men’s tees: 119 and the ladies’ red tees perhaps a 114.
These figures are almost always printed on the score card in the United States. Course Slope is a creation of The United States Golf Association and has been licensed to the Royal Canadian Golf Association. Courses outside of the United States and Canada (and their protectorates) will probably not have a Slope rating.
What is the definition of a “par golfer”?
Someone who consistently shoots par for the course, regardless of the course. Also known as a “scratch golfer”.
What is the definition of a “bogey golfer”?
Someone who shoots 18-over-par on average. I.e., this golfer would regularly shoot a score of 90 on a par-72 regulation course.
Why are there two numbers to describe the difficulty of a golf course?
Ever notice that the professionals on television always seem to shoot in the low 70s or high 60s no matter how easy or difficult the golf course is?
In the 1980s, The USGA noticed this too. Statistically, they could show that no matter how easy or difficult a course was, the very best of golfers will still shoot a score close to par.
But they also noticed that the scores of less-proficient golfers were more strongly affected by the difficulty of a golf course. And in general, the worse the golfer, the more that golfer’s score was likely to be affected by the difficulty of the course itself.
And so, the handicap system was revised in the late 1980s to include a second figure to describe the difficulty of a golf course. This figure is known as The Slope.
The Slope is actually not a measure of a course’s difficulty. That’s the responsibility of The Rating figure.
The Slope is a measure of how much difference a course’s difficulty is for the average bogey golfer compared to the scratch golfer.
For example say two different classes of golfer played a Course.
A dozen par golfers played this course under different weather conditions and different pin placements over and over and over again. On average, they shot a 72.
A dozen bogey golfers also played this course over and over and over again. Their average score was 90.
If we draw a straight line between these two values, you’ll see that the line ramps upwards from left to right. Remember your first algebra class? The amount of slant in this line is called the “slope”. The amount of slope indicates just how quickly a course becomes difficult for a golfer who is not as good as a par golfer.
And this is how the Course Slope figure gets its name.
Let’s continue this example:
The Course Rating is simply the average score compiled by the par golfers. In this case, it’s 72.
However, the Course Slope is not simply the average score compiled by the bogey golfers. The value for Course Slope is a measure of the amount of slant (or slope) in the straight line drawn between the two values.
The values for Course Slope run from 55 to 155. The units are unimportant. Suffice to say that The USGA has developed a scale that is conducive to manipulation with a standard hand calculator. Because this course is very ordinary, we’ll say that the Course Slope is 113 for Course 1. 113 is the USGA’s standard slope value.
Now 16. We took these same par and bogey golfers to Course 2 and let them play hundreds of rounds.
The average score of the par golfers was 68.5. Therefore, the Course Rating is 68.5. It’s an easier course for par golfers to play.
The average score of the bogey golfers was 86.5. The slant of the line drawn between these two numbers is precisely the same slant as was obtained on Course 1. Therefore the Slope of Course 2 is actually the same as the Slope of Course 1, which is 113.
Now consider a 3rd Course.
Once again, the average score for the par golfers is 68.5, making the Course Rating 68.5.
But Course 3 is extra difficult for bogey golfers. Perhaps this is a very long course, one that won’t faze professionals. But the added length may prove too much for the typical bogey golfer.
When we look at their scores, we find that the average is close to 92.
Drawing a straight line between the values results in a greater slant than we found with Course 1 and Course 2. I.e., the Course Slope is greater.