.In 1977 Lt. Commander Dean Knuth of the Naval Post-Graduate School proposed an improved system that involved numerical rating of 10 characteristics for each hole. These ratings, along with the weighted factors for each characteristic, provided an adjustment to the distance and rating of the course. The basis of this system was used to create the current USGA Course Rating System. In 1978 Dr. Richard Stroud proposed the concepts of the Slope System. Eventually the concept of Scratch Ratings and Bogey Ratings crept into the formulas and course rating became a two-number procedure in 1981.
In 1982 and 1983, under the leadership of Dr. Byron Williamson, the Colorado Golf Association pioneered the new Rating System and rated all its courses using the new procedure. The tests that Colorado performed using the Slope System for the USGA had positive results. The following year, five other states joined Colorado and others followed in subsequent years. Slope Ratings were implemented by the USGA on January 1, 1987. Slope Ratings assist in addressing the problem of portability of handicaps and adjusts a player’s USGA Handicap Index according to relative difficulty of the course being played.
The USGA established a USGA Course Rating Subcommittee in 1987, which includes golf association staff and volunteers interested in the policies of the USGA Course Rating System. The committee meets annually to discuss modifications to the system and since 1989 conducts national course rating calibration seminars for all associations and foreign countries licensed to use the system.
Today the USGA Course Rating System is accepted as the gold standard for determining the difficulty of a golf course. More than 60 countries around the world are licensed and trained to rate golf courses using the USGA Course Rating System.