The Relative Value of Age: Comparing 90’s to Today

Youth is often described as both a commodity and a liability in the NBA. A “divine treasure,” sure, but there’s also a lot of talk to suggest that being young and being elite are mutually exclusive. The Jazz are caught in that dichotomy right now, with a young core that, depending on who you believe, will either be propelled or limited by its innocence.

But age, like most things, is relative and the context of larger age trends can make it matter more or less. To use a parallel example, George Mikan’s size (6’10”, 245 pounds) was a lot more imposing in the ’50s when the average NBA player was 6’4″ and 195. Today, his average peer (6’7″, 218) would make him seem far less physically dominant. That’s why we remember Mikan as a hulking behemoth, while we imagine Al Horford very differently despite identical listed dimensions. Context made Mikan bigger.

Couldn’t the same be true for age?

This first struck me as we’ve been discussing expectations for rookie Trey Burke relative to “older” rookies in the 22+ range, but the idea of relative age could be important to the team as a whole.

The five players commonly referred to as the Jazz’s core of recent lotto picks will have an average age of 22.12 on opening night. I wanted to see how much that mattered today versus in the past to examine whether our frame of reference is outdated for lowering expectations based on being a certain age instead of a year or two older.

The folks at basketball-reference.com made the first data cut fairly easy. The league was, in fact, older for most of the last 20 seasons, topping out at an average age of nearly 28 years old in the late ’90s. This is after an upward trend coming out of the post-merger area that can likely be attributed to better injury prevention and anti-drug programs. A lot of careers were ending early back then due to some combination of bad joints and nose candy, but suddenly in the ’90s, careers were going longer and the average age was moving up. This is the case until the turn of the century, when we start to see a defined drop..

Interestingly, while the age limit imposed for the 2006 Draft (indicated with a vertical grey line) did slow the downward trend, it didn’t actually increase average age in the long run.

So 21-year-old Burke is actually older relative to the average NBAer (26.7) than a 22-year-old rookie was in 1998 compared to his 27.9-year-old average peer. Seen through that lens, the Jazz’s 22-year-old core isn’t as young as it seems in a greener league.

But what about the core of the NBA? Overall average age could be the result of a trend giving younger players a larger chance at fringe roles over their older counterparts. So I was also curious to see how the age distribution looks among real impact players.

This required a little more calculating, but I added to the graph the average age for just players with 5.0 win shares or more in the same years. Why 5.0? That is one of those natural breaking points that really passes the nose test. Guys with 5 WS or more are generally part of good teams’ cores and, without exception in this 20-year sample, are the top 80-100 in the league. (I did proportionally adjust the WS requirement for the two lockout seasons.)

Even in a more mature NBA in the ’90s, the average impact guy skewed older than the general population. Some of this could be because those stacked draft classes of the mid-’80s were reaching their best years, but for whatever reason, the league was not very dependent on its youth. If you were a top-three player on an NBA team in the Clinton era, chances are good you were closer to 30 than to 20.

That gap started to close after the 1998 lockout, and then the trend changed completely from 2003 forward. In fact, the age of impact players has been falling on an even steeper slope than the overall age trend. There have been four years where the average impact player was younger than most of his peers. And lest we assign all the credit to the stellar draft classes of ’03, ’05, etc., it’s worth noting that in the four years where the average good player was younger than the average player, only 1-3 rookies each year made that WS 5.0 cut. Translation: it isn’t just LeBron (5.1 rookie WS, barely making the cut); the league is relying more on youth overall.

Here are a couple of time-lapse graph to show that being young today isn’t quite as big of a liability as being young 15 years ago.

Not only has the sub-25 crowd become a lot more prevalent in the last two decades, they’re also accounting for far more of the wins. In the three mid-90s seasons on that graph, there were right around 100 guys in the league who hadn’t turned 25 yet, and they accounted for less than a fourth of the total wins (per WS) in the league. The last three seasons have seen half again as many players in that demographic (about a third of the NBA is 24 or younger), and they’re now accounting for over a third of the wins.

For this graph, I chose ’97 because Tim Duncan distorted the ’98 sample with an insane rookie WS and ’99 was a lockout year.

The thing that should first grab your attention is how, once you’re past 25, it’s considerably harder to stick in the league than it used to be (bar graphs). Where the 25+ crowd used to make up about 75% of the league, now they’re barely 60%.

But there are some funky things happening with the lines, too. An NBA player in the 31-33 age bucket in 1997 had an average WS that was literally double his average 22 to 24-year-old counterpart. Last year, the value of those two players was equal.

The 18-21 year old bucket has become shakier ground, but that’s probably due again to context. In the ’90s, the players who were selected out of high school or as underclassmen were generally star-level players. Today, it is far more common for even second and third-tier collegians to declare young, and for NBA teams to draft them on potential. That age bucket also has the smallest sample size, so a couple of young guys who are being shelved for future use will really bring this average down.

However you slice it, this league is increasingly populated with younger players who are making an impact earlier in their careers. That doesn’t necessarily mean that all of Utah’s youngsters are destined to become instant stars. But it does mean that, in the context of a younger league, the inexperience of the Jazz’s core won’t stick out as much as it would have 10-15 years ago.

If Mikan’s era made him bigger than his Horfordesque frame, then by the same logic the young man’s league on 2013 is about to make Burke & company older, and the Jazz will have to ride their steep learning curve to some quick improvements.