The term ‘slope’ is perhaps the most discussed and, at the same time, the vaguest term in the golf terminology. Even if you are clueless about golf’s USGA rules, you have probably come across the term at some point. Several myths and misconceptions also cloud its meaning and relevance that even experienced golfers hit a wall when they need to interpret it adequately.
Course ratings and slopes are often considered the same, particularly when discussing a player’s index and handicap. Since USGA course rating system clearly distinguishes slope from course rating, we felt that we needed to address the question and clear out the dilemma of, ‘What does the slope of a golf course mean?’
A golf course slope is a USGA designated rating number that indicates the difficulty of a specific course for bogey golfers. This number is used to calculate a player’s handicap index. The value is between 55 and 155, and the average standard slope number ranges from 113 to 120. The higher the slope number, the more difficult the golf course is for average golfers.
USGA introduced the slope rating measurement in the 1980s as a system of fairness directed to bogey players. Namely, they observed that a bogey golfer is likely to increase the number of strokes considerably more when playing on a course with a higher level of difficulty than a scratch golfer. This led to creating a slope handicap system that is intended to offer equal opportunities for all players.
However, when playing or watching tournaments, you’ll notice that two numbers refer to the golf course rating, and this is what we will discuss next. We’ll point to how golf course rating is calculated and how it relates to the course slope.
How Is the Course Slope rating Calculated?
The standard procedure to calculate the slope rating is to multiply the difference between the bogey rating and the USGA score rating. The score you get when the expected good score for a Scratch golfer (a zero handicapper) is multiplied by the expected good score for a bogey golfer (a Mid handicap golfer with a range from 18 to 30).
Thus, the slope number converts a golfer’s handicap into a course handicap. In this way, it is made sure that a bogey golfer is allowed to play at an equal level to a scratch golfer, and it helps them obtain enough strokes from the same set of tees. This is the mathematical formula of how it is derived:
Slope (men) = 5.381 x (bogey rating – USGA course rating)
Slope (women) = 4.24 x (bogey rating – USGA course rating)
So, once the golf course is rated, the bogey rating and the scratch rating are determined for each set of tees, leading to determining the slope number.
What is USGA Golf Course Rating and Who Rates It?
USGA Golf Course Rating is an assessment of the difficulty of a given golf course for scratch golfers. The course rating estimates the scratch golfers’ average scores who played on the golf course under the rating procedure. It is expressed in strokes, so an easy par-72 golf course could have a 68.9 course rating, while the more difficult one is likely to have a rating of 74.5.
In other words, an average golfer should expect to play 68.9 strokes when the course playing difficulty is rated ‘easy,’ while on a challenging course, the same golfer is expected to average 74.5 strokes. On the other hand, as we have seen above, the slope rating is not related to the number of strokes played at the course in question.
Therefore, the course rating provides scratch golfers information about the course difficulty, while the slope rating delivers the same information to bogey golfers. In other words, the USGA slope rating indicates the additional playing difficulty of the course for average golfers compared to scratch players. The dominant factor that defines the course difficulty is the golf course rating, not the slope rating.
Every golf association has a course rating team that has passed USGA’s Course Rating System regulations regarding the rating procedure.
What Is the Minimum and Maximum Slope Rating?
The minimum established number for a slope rating is 55, while the maximum is 155. The difficulty is proportional with the number, i.e., the lower the slope rating, the less difficult it is. The United States Golf Association established the average slope rating to 113, but it has later increased to about 120 as there aren’t many 18-hole golf courses with slope ratings set that low. As has been observed, most golf courses worldwide have average slope ratings of about 120.
What Factors are Considered When Rating a Course?
When rating a course, five factors are considered: elevation, dogleg/forced lay-ups, roll, wind, and altitude. Plus, nine physical and one psychological obstacle are also assessed: water, trees, green target, green surface, fairway, topography, bunkers, extreme rough, regular rough, and recoverability. To maintain objectivity, the assigned values by the USGA Course Rating Guide are taken and considered.
When rating the course, the team evaluates the landing area for a bogey golfer the first 200 yards off the tee. They measure the width of the fairway, consider any existing bunkers, and estimate the distance from the fairway center to the nearest boundary/hazard line or trees. The same measurement is applied for scratch golfers, adding 50 yards to the landing area off the tee. The process continues until the team reaches the green. There, the rating team measures the depth and the width of the Putting green, the bunkers and the water hazards, and the distance to the boundary line.
The above-mentioned process is applied to every tee and every hole. When the measurement data has been obtained, (unlike the measurement used on a Rangefinder with slope) raters get the ratings for scratch and bogey golfers. Once they have them, then they proceed with the mathematical formula to calculate the slope number.
Do Slope and Course Rating Affect Golfers’ Handicap?
Yes, they do. However, the course rating impacts the golfer’s index considerably more than the slope number. It often happens that players become too focused on the slope number while ignoring the golf course number. It is important to note that if a certain course number is high, and some golfers might find it too competitive, it won’t necessarily mean that they won’t be able to play on another course. The formula below shows the significance of the course rating on the players’ handicap differential:
Handicap differential= (Adjusted Gross Score – Course Rating) x 113 / Slope Rating
Being able to read the greens is critical to your putting success. We have secured a up to 50% off deal with Strackaline, the #1 Green Reading Book in Golf.
Click here to see if your home course is available.