Golden Ages of Basketball Players
The simple rule of life: everything arises, improves, declines and ends. Both the living creatures and all the processes around obey this rule. The basketball players’ career trajectory is not different at all. They enter the league as rookies, they adapt and improve their plays physically, mentally and even in terms of abilities, but then someday a decrease of performance begins due to advanced age and finally they quit the professional basketball.
The age (so the experience) is a very important factor to precise the performance levels of players in all physical sports. For example when a team drafts some young prospect, they sometimes leave this player overseas or send it to D-League with the aim of finding greater opportunity to develop himself by playing in relatively low level.
Or when a player gets older and his performance drops, teams choose to waive/amnesty/send him away. The question is when does the prime of a basketball player begin? It lasts how many years? And does it differentiate according to basketball positions? These questions are important because they define the GMs’ strategies in terms of contract negotiations, drafts, trades and all other player involved decisions.
In this analysis, we will scrutiny the relationship between the performance and age of NBA players starting by the season 1997-98. For performance, we are using an in-game efficiency score metric calculated using seasonal total player stats with the following formula: PTS+(FGM-FGA)+(FTM-FTA)+REB+AST+STL+BLK-TO. Then, we found the average of each player’s efficiency score per game played. The playing time is also an important factor. So, we also looked to the per 36 minutes efficiency score. Finally, if the total matches played of that age group of players are below %10 of maximum match played age group, then it is excluded from the graphics, as they can’t provide reliable statistical data.
Age vs. Efficiency
The following table summarizes players’ average stats and efficiency scores grouping by the age factor. The ages of 19, 39, 40 and 41 are excluded due to small number of games played by players of that age.
Just note that, regarding the last 17 NBA seasons, the youngest player’s age is 19 (Tracy McGrady in 1997-98 with Toronto Raptors) and the oldest one is 41 (Karl Malone, 2003-04, Lakers; John Stockton, 2002-03, Jazz; Dikembe Mutombo 2006-07, Rockets; Kevin Willis 2002-03, Spurs and Clifford Robinson, 2006-07, Nets).
The age – efficiency score curve can be depicted such as:
We are seeing that 29 years old is the most efficient age in NBA basketball. And the prime years for a players are between 26-29 years old. A clear performance drop can be seen starting by age 31, and 22 years old is the starting point to play effectively.
Interestingly, there is an unexpected rise of performance after 36 years old. But this is due to the fact that, at such age, regular players quit playing and mostly star or superstar level players try to continue their careers. Some examples players who remain in the league after 37 years old are Karl Malone, Tim Duncan, John Stockton, Steve Nash, Patrick Ewing, Jason Kidd, Shaquille O’Neal, Grant Hill, Hakeem Olajuwon, David Robinson, Scottie Pippen, Reggie Miller, Kevin Garnett etc. In per 36 min stats, the performance drop after age 30 is more evident since this graphic omits the effect of better players staying more on court.
Does the Position Matter?
Let’s look at the same age vs. efficiency graphs according to the basketball positions: guard, guard-forwards, forwards, forward-centers and centers.
We are seeing that the prime years of guards is 28-32 years old interval. This shows that guards mature a little bit later than other players. The basketball intelligence, ball conservation, court vision, shot mechanics are all skill peculiar mainly to the guards and correlated with experience. On the other hand, per 36 minutes graph indicates another aspect: guards are also very effective at younger ages (23-25) but their playing time are limited comparing to later ages.
GUARD – FORWARDS:
22-23 and 27-29 years interval are the most effective ones for guard-forwards. Since the athleticism (quickness, endurance and explosiveness) is a very important part of this position, 22-23 years old period makes an unexpected outlier. But note also that overall efficiency score averages of those position players are the least across all other positions’.
This graph is very similar to the first one (all positions overall graph). Thus, the prime ages of forwards are 26-29 years old, and the performance level drops after age 30.
FORWARD – CENTERS:
Here are the most unexpected age-efficiency graphs. But of course for good reason. If we omit the age 21, we can interpret that the prime years for this position is 26-29 and there are a continuous drop of performance afterwards.
But why the age 21 is an outlier? Because there are relatively few number of players in this categories and most of them enters the league at age 22 or later. But some special talented ones enter the league one or two years earlier: Anthony Davis, Chris Bosh, Amar’e Stoudemire, Kevin Love, Greg Monroe, Nene and Serge Ibaka. Pretty elite group of players huh?
For centers, there are many zigzag patterns in the graphs, but we are seeing that the prime years are longer than any other position (between 26-34 years old). We can say that for centers the size and power or the two important factors that do not disappear at early 30s.
What about Best performers’ Age Curves?
In order to see the striking effect of age on performance, let’s examine the graphs of some best performer players according to positions. The blue line will represent the seasonal efficiency score per game of players with their normal playing time. And the orange one, normalized according to per 36 minutes.
Kevin Garnett – Forward-Center
Kevin Garnett passed his prime years between 27-30 years old. At that period he leads all the players in the league with 30+ efficiency point per game. But especially after 33 years old, his performance starts to drop. Although his per 36min effectiveness still acceptable at age 38, both his playing time and so the efficiency points are under the league average with a value of only 9,34.
LeBron James – Forward
Have LeBron James’ prime years ended? No clue yet. But his playing time is decreasing (for conservative purposes) and we can affirm that we are seeing his prime years starting his 25. If there won’t be any injuries, LeBron most probably will perform with around 30 efficiency points per season in the next 4 years.
Shaquille O’Neal – Center
As our data start by 1996-97, Shaq’s age vs. efficiency graph begins at age 26. And also in 2006-07 season (age 35) Shaq played only 40 games in Miami Heat, and the following season (age 36) after playing 33 matches with the Heat, he got traded to Phoenix Suns and finished the season there with 28 games. So these two season performances are omitted due to not being reliable statistically.
Shaq’s prime years were at age 27-31. And after 33 years old his efficiency lessened.
Tim Duncan – Forward-Center
At age 26-27 Duncan was the most dominant. But there is no well defined prime years window for him, because he is amazingly and unbelievably consistent. Even though his efficiency score dropped a little bit after 35 years old, he somehow succeeded to raise it again at age 37!
Kobe Bryant – Guard
Kobe Bryant prime years were between at age 25-30. But he still performed very well at age 35. Just note that age 36 (2013-14) season excluded as Kobe did only play 6 games. Kobe’s production could be estimated around 17-18 efficiency score per game at age 37 if healthy. But we are seeing his last seasons in NBA.
Dirk Nowitzki – Forward
Dirk Nowitzki played only 50 games and 19.2 minutes per game in his first season in NBA (at 21 years old), so this age seems an outlier. His prime years are between 25-32 years old but he can still perform in high level despite reaching 36.
Steve Nash – Guard
Surprisingly Nash’s efficiency score are very low in his first seasons. At age 24 in Phoenix Suns, he barely could play; and after traded to Dallas Mavericks his performance was mediocre at best in his first two seasons. But then some miracle happened, and Nash started to perform at MVP level. He selected two times MVP indeed at age 31 and 32.
Regular Season MVPs’ Ages
Before concluding the age vs. the performance chapter, we also looked at regular season MVP’s ages. The following table shows the MVPs of last 17 NBA seasons with their efficiency per game averages.
Derrick Rose is the youngest MVP of NBA for all-time. He selected to this honor at age 23. But in fact, in that season there are 10 other players with higher efficiency scores and the lead performer was LeBron James. We know that being the best performer is only one of the criterion in MVP votes (the team success is the other most important).
In 7 of 17 times, the best performer was selected MVP. Two must arguable MVP selections are Allen Iverson’s 2000-01 season and Steve Nash’s 2004-05 season where there are 8,55 and 11,76 efficiency score per game differences respectively between them and the best performer’s.