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Weekly Quiz!

To see the correct answer, click the “CONTINUE” button at the bottom of the next page.

Good luck! 😀 

How Bad Are Your Bad Rounds?

Let’s talk about your worst rounds.

We’re not talking about that one triple you made after the turn. We’re talking full-on disaster rounds… the ones that leave you standing on the 18th green wondering if you’ve ever played golf before.

Thinking about how well you played simply by looking at your score can be misleading…

An 85 from the tips at Kiawah Ocean Course is very different than an 85 from your local 6100-yard muni. To compare rounds across different courses, we need to look at your differential.

What is a differential?

A differential is a way to measure how well you played accounting for course difficulty. It factors in course rating, slope, and your score. (Yes, there’s also something called PCC, Playing Conditions Calculation, but we’re not using that here.)

Think of the differential as a normalized score. Your net differential is simply the differential for that round minus your handicap index.

For example if a 12.0 index played a round where the differential was calculated to be 16.4, the net differential would be 4.4

16.4 - 12.0 = 4.4

Example: Same score, very different performance

Let’s walk through two players:

Player A: 0.0 Index

• Shoots 80 on a course rated 70.8 with a slope of 128
  → Differential = 8.1
  → Net differential = 8.1 − 0.0 = 8.1

• Shoots 80 on a course rated 76.4 with a slope of 147
  → Differential = 2.8
  → Net differential = 2.8 − 0.0 = 2.8

Player B: 10.0 Index

• Shoots 90 on a course rated 70.8 with a slope of 128
  → Differential = 17.0
  → Net differential = 17.0 − 10.0 = 7.0

• Shoots 90 on a course rated 76.4 with a slope of 147
  → Differential = 10.5
  → Net differential = 10.5 − 10.0 = 0.5

Same scores for each player. Very different net differential. The smaller the net differential, the better you played. Your really bad rounds will have a larger net differential.

So what does a really bad round look like?

The chart below shows the 5th percentile net differential across different handicap levels and course ratings.

In plain English:
Only 5% of rounds have higher (worse) net differentials than the numbers shown. 95% of rounds are better (lower net differential).

For example, let’s take a look at the 0-index player. On courses rated between 70.0 and 70.9, their 5th percentile net differential is 9.1. That means 5% of their rounds will have a net differential that is worse (higher) than 9.1.

Remember, the larger the net differential, the worse you played.

Interesting Note:

As course rating decreases (the course gets easier), the 5th percentile net differential gets worse across all skill levels.

Final Thought

You’re going to have really bad rounds.

Even the best players in the world do.

The next time you post a round that feels like a trainwreck, remember:
You’re not alone… and the data says it’s completely normal.

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