We use the same formula as the USGA. The following steps are
taken to calculate it.
First, we calculate the handicap differential for each round
using the USGA Course Ration and Slope Rating for the courses
HCP Dif=(Score - Course Rating) x 113 / Slope Rating
Example: Your score is 85, the course rating
is 72.2, and the slope is 131.
The formula would be (85 - 72.2) x 113 / 131.
This differential is calculated and recorded for each
The next step is to figure out how many differentials to use.
Only the lowest differentials are used. If you've only entered
11 rounds then only the 4 lowest differentials are used. See
the following chart:
Number of Differentials Used
Next, we find the average of the differentials used. If we're
only using the 4 lowest then we add them together and divide
by 4. We then multiply this by 0.96. All the digits after the
tenths are dropped (not rounded) in the result. This gives us
your handicap index.
HCP (handicap) index = (sum of differentials/#
The HCP index is used to find the course handicap. This is
because course difficulty varies and your handicap on one
course may not be equal to your handicap on another.
the Course Handicap
The course handicap is calculated using your HCP index and
the Slope Rating of the Tees Played divided by the average slope
rating of 113.
Course Handicap=(Your HCP Index) x (Slope Rating of
Example: You have a HCP index of 16.7 and you played a
course with a tee box slope of 127.
Course HCP = 16.7 * 127/113 = 19 (Course Handicap is rounded
up or down)
In this example the course you played is harder than the
average course which is why your course handicap (19) is higher
than your handicap index (16.7).
The Course Handicap is the number you use to determine how
many strokes you get.
Equitable Stroke Control (ESC) is the system put in place by
the USGA to eliminate the effect of "distaster holes." You know,
that one hole per round where you put three balls in the water
and then 5-putt. It's also a way to combat those pernicious
sandbaggers who intentionally blow up on a hole in order to
raise their handicaps. Equitable Stroke Control puts a limit on
the number of strokes you can write down on the scorecard for
any one hole, based on your course handicap. For example, on
that one disaster hole you might have taken 14 strokes (get to
the practice range, buddy!) to get the ball in the cup. But
based on your course handicap, ESC might require you to post
only a "7" on the scorecard you turn in.
Taking the "14" might throw your handicap index out of whack.
And remember, the handicap index is not meant to reflect your
average score, it's meant to reflect your best potential.