How Much Deeper Has Golf Become In The Last 25 Years?

This question is one that is very relevant for a variety of reasons. However, the reason I wish to explore this question is to help aid golf fans (and analysts) who wish to compare achievements across generations of professional golf. It is not uncommon to see people carelessly compare golfers between generations by simply looking
at number of wins.

A typical analysis is the following:
Jack has 18 majors, Tiger has 14, therefore Jack is the best golfer of all time.
Needless to say…this kind of talk needs to end.

In order to investigate if/how much golf is getting deeper, we need to come up with a few different ways of measuring “depth” in golf. Note that these measures cannot be related to changes in actual skill level over time, just the relative dispersion of skill level over time.

Difference between CUT LINE and LEADERS after 36 Holes

If golf is getting deeper, one would think that the number of shots between 36 hole leader and the cut line would be smaller than it used to be (since competition should be stronger). Below is a plot of the averaged number of shots separating the leader and the cutline for each year since 1983.

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Of course, we do see the separation decreasing over time, but not by much.In 2015-16, the cut is on average 1 shot closer to the lead after 36 holes than it was back in 1983. So there is some bunching, but not as much as we would expect to see.

Perhaps it makes more sense to look at the distance between 5th place and the cut line. This way, we don’t have individuals who are leading the field by 4-5 shots through 36 holes skewing the data upwards. Below is the same plot, but showing the difference between 5th and the cut line.

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Again we see the downward trend indicating more bunched leaderboards heading into the weekend. Not a very large difference between the early data and the more recent years (only a  bit less than a shot).

So, while we do see that leaderboards are more bunched since 1983, the trend is much weaker than we expected.

Number of Players with AT LEAST One Top 10 Finish Per Year:

If golf has been getting deeper, we would expect to see more and more players contending over the course of the year. If more players register a top 10 each year, it just simply means that the pie of pro golf is being split into thinner and thinner slices. It would also suggest that the “anyone can win” rhetoric we hear from players has truth to it. Below is the plot that tracks unique top 10 finishers per year since 1983:

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We can see that there has been a steady upward trend in the data. More and more players each year are entering the conversation by registering at least one top 10. In 1984, there were 138, the number of players with a top 10 in 2010 was 195, an increase of 41%.

To put it simply, there are just more cooks in the kitchen now than there used to be, and that is going to make it harder to do anything, whether it be making the cut or trying to win.

Variance of Scoring Averages

This last measure is pretty simple, I am simply looking at how variable the scoring averages are by year. The more variance there is, the wider the range of talent on tour that year. So as variance goes to zero, we approach all players having the same scoring average. If the PGA Tour is getting deeper, we should see scoring average variances falling over time. The plot is shown below, and only players who played at least 20 rounds that year are included in the calculation.

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Here is proof that the talent level on Tour is really bunching up. In the 80’s, the variance of scoring averages was much higher than it is now, and it is decreasing very steadily. Variance is pretty much half of what it used to be. What this means is that the relatively good players aren’t as good anymore, and the relatively bad players aren’t as bad.

So what have we learned here?

Basically, there are 3 measures of PGA Tour depth analyzed above. All 3 show that the Tour is becoming deeper, and it does not appear that this trend is stopping.

To me, this means that given you are on the PGA Tour in 2016, you are going to have a much harder time making cuts and contending than if you played on tour in the early 80’s, due to the bunching of talent.

So next time you want to compare Jack to Tiger (or even Tiger to Rory/Jordan/Jason), remember that as time moves forward, it is getting harder and harder to win. Jack had to worry about a lot fewer legitimate players than Tiger, who had to worry about fewer legitimate players than Rory.

To hammer this point home, if this trend continues, the 2060 Player Of The Year might only have a win or two, instead of 4 – 5 that we see today, because everyone will be so good.

Please keep this all in mind when you are having GOAT conversations, in any sport.