(Quoted from "Handicapping News", Spring, 2005, p.3)

Does it seem that you play a few strokes over
your Course Handicap most of the time? Well that's normal under the USGA
Handicap System.

Why? The USGA Handicap System is based on the potential ability of a player
rather than the average of all of his scores. The USGA's Handicap Research
Team tells us the average player is expected to play to his/her course handicap
or better, 25% of the time.

(The following is quoted from the magazine GOLF FOR WOMEN, May/June 2005,
p. 99)

Slope/Course Rating
The USGA developed a “course rating” system for courses in America. This rating
assesses a course’s playing difficulty based on what a scratch golfer would shoot
under normal conditions. Most ratings are around par (72). If a rating is 74.6, the
course will play a little tougher; if it’s a 68.7, your day will be a bit easier. The
“slope” indicates an average player’s potential scoring ability on the course. The
lowest slope rating is 55 (an easy course), and the highest is 155 (very difficult).
A golf course of standard difficulty as defined by the USGA, has a slope of 113.

Handicap Index
Because golf courses vary in difficulty, the USGA establishes two numbers for
every golfer: a handicap index and a course handicap. When people ask your
handicap, it’s really your index they’re asking about. (This is the number with a
decimal point that the computer spits out after you post each score.) The index is
based on the best 10 of your most recent 20 scores and expresses your potential
scoring ability.

Course Handicap
This is the number of strokes allotted to you for the particular course you’re
playing, based on its relative difficulty. Your index and the slope of the tees you
play from determine your course handicap. Most pro shops have a chart that
does the conversion for you. Or you can simply multiply your handicap index by
the slope and divide that number by 113. For example, if your index is 26.4 and
you’re playing from the tees with a slope of 120, your course handicap is 28 (26.4
x 120 )[divided by] 113). The average golfer plays to her or his course handicap
25 percent of the time and plays a few strokes over it most of the time.