A while back, I tried my hand at some golf ratings. (Back in the day when Sergio Garcia was playing good golf.) It was a fun experiment, but ultimately it was such a task to gather data for such a project that it was impossible to maintain.  At any rate, there are still fun things to do with golf stats and with the US Open days away, it’s a good time to explore some of these things.

Unfortunately, the PGA Tour is far too possessive with its data to tackle a lot these things. However, the money lists are fair game and easily accessible. While there’s a limit to the information that comes from the money that a player earned over the course of a golf season, the primitive state of golf analytics is such that there’s some valuable info to be mined from this.

For instance, there’s very little attention given to quantifying a professional golfer’s performance over the course of a season. A simple way to assess how well a golfer played during a particular year is to use the money list. The problem comes with comparing performance from different seasons because inflation in tournament purses has been pretty impressive. Below is the average prize won by the top 125 players on the money list each season since 1970.

Prizes rose exponentially in the 70’s and 80’s before leveling off in the early 90’s and then exploding again for a 15-year period before the recent stagnation since 2008. Obviously, one has to take this into account when evaluating a golfer’s performance based on money earned.

A crude but effective way to measure performance is to take the ratio of the average prize earned by a particular golfer (total money earned divided by events played) to the average prize earned by the top 125 in a particular season. I’ve multiplied this value by 100 to give us nice whole numbers and branding this metric the Golf Performance Rating. Values of GPR greater than 100 indicate a player that played better than your average Tour member.

I’m not going to sell this as some sort of rock-solid measure of golfing ability, but it seems to hold up well across eras. I have all of the PGA Tour money lists since 1970 (thanks to databasegolf.com, pgatour.com, and yahoo.com) and I hope to have previous years compiled soon. (Edit: Thanks to Neil Paine at sports-reference.com for supplying me with earnings information for previous seasons. You should visit his site often for historical college hoops data. I have updated the chart below to include all years back to 1960.)  One thing I thought would be interesting is to determine which player had the best season at a given age. For purposes of this study, I am taking a player’s age for a particular season on July 1 of that year. Here’s what I got for the best GPR for players that participated in at least ten PGA events in any season.

Age         Best        GPR               Second Best   GPR      
19   1999 Sergio Garcia 246*               
20   1996 Tiger Woods   379         2000 Sergio Garcia 163
21   1997 Tiger Woods   473         1973 Ben Crenshaw  429
22   1998 Tiger Woods   353         1962 Jack Nicklaus 319
23   1999 Tiger Woods   888         1963 Jack Nicklaus 550
24   2000 Tiger Woods  1125         1964 Jack Nicklaus 423
25   2001 Tiger Woods   651         1965 Jack Nicklaus 531
26   2002 Tiger Woods   770         1966 Jack Nicklaus 445
27   1974 Johnny Miller 776         2003 Tiger Woods   646
28   1978 Tom Watson    547         2004 Tiger Woods   453
29   2005 Tiger Woods   785         1979 Tom Watson    654

30   2006 Tiger Woods   991         1980 Tom Watson    699
31   2007 Tiger Woods   947         1971 Jack Nicklaus 738
32   1972 Jack Nicklaus 937         1962 Arnold Palmer 521
33   2009 Tiger Woods   835         1973 Jack Nicklaus 806
34   1974 Jack Nicklaus 657         2004 Ernie Els     585
35   1975 Jack Nicklaus 867         1990 Greg Norman   552
36   1976 Jack Nicklaus 702         1972 Gary Player   628
37   1977 Jack Nicklaus 623         1994 Nick Price    499
38   1978 Jack Nicklaus 653         1993 Greg Norman   617
39   1989 Tom Kite      540         1994 Greg Norman   526

40   1995 Greg Norman   596         1980 Lee Trevino   532
41   2004 Vijay Singh   608         1971 Arnold Palmer 474
42   1997 Greg Norman   431         2005 Vijay Singh   425
43   1983 Jack Nicklaus 386         1993 Tom Kite      302
44   1984 Jack Nicklaus 398         1975 Gene Littler  382
45   1990 Hale Irwin    397         2001 Scott Hoch    265
46   1996 Tom Watson    268         2003 Nick Price    236
47   2008 Kenny Perry   255         2002 Loren Roberts 155
48   1960 Sam Snead     303         2009 Kenny Perry   254
49   1992 Ray Floyd     374         1961 Sam Snead     303

50   2004 Jay Haas      146         1962 Sam Snead     123
51   1963 Sam Snead     298         2007 Fred Funk      79
*Garcia played 9 tournaments in his age-19 season, the most of any 19-year-old

The two dominant players of this era expectedly dominate this list. Tiger Woods ranks first at every age for which he qualifies through age-33 with the exception of age-27 and 28 “slump” where he ranks second. His age-32 season consisted of six events so he doesn’t qualify here, but based on those he had a rating of 1370.  He led the tour in victories despite the very limited schedule.

Of course, last season he played enough events to qualify for the list (17), but only managed a rating of 144. “Only” is relative here, and for almost any other player, a mid-career slump is much, much worse than this. Take Steve Stricker, who posted the third-best season by a 43-year-old last season and is currently the top-ranked American player. This is how his rating has evolved with age since he joined the tour as a 27-year-old.

In what would normally be the tail end of Stricker’s prime – his age-35 through 38 seasons – he entered 90 PGA events and missed the cut more often than he made it while posting just three top tens.

One of the problems with the PGA money list is that it excludes prominent players that spend most of their time on the European Tour. Thus, I have no data for the current world number-one (and US Open favorite) Lee Westwood, who experienced a similar slump in 2002 and 2003.

A mid-career slump isn’t unusual, and Woods’ drop-off, external factors aside, isn’t particularly alarming in his quest to break Nicklaus’s record of 18 major championships. However, it should be mentioned that Woods’ 2010 season was worse than any season Nicklaus experienced between age 30 and 46. Because my data only goes back to 1970, I don’t have ratings for Nicklaus in any of his pre-age-30 seasons yet, but this is what the data for Jack looks like beyond from age 30 onward. (Note the vertical axis spans twice the values of Stricker’s.)

Nicklaus’s “slump” year was at age 39, when he only played in 13 tournaments and recorded just six finishes in the top 20. I hadn’t really followed Nicklaus’s career, but by GPR he was still one of the best five golfers on tour in his early-to-mid 40’s and displayed remarkable consistency through age 46. He just played so few tournaments by that time that it wasn’t reflected on the money list. Winning the Masters in ’86 wasn’t the late-career fluke I was under the impression it was.

Wednesday, I’ll get to the issue of whether there is any hope for Tiger catching Jack’s majors record, but tomorrow we’ll take a look at what success at an early age means and whether we can expect Rory McIlroy to be the next double-digit winner of majors.