Even the most irrational LeBron hater has to admit that the 2014 Cleveland Cavaliers are eminently more exciting than the Miami Heat superteam that dominated the Eastern Conference from 2010 until this last summer, although the script, that James left a roster with some insurmountable holes to pair up with a couple of All-Stars in order to cement his legacy, is largely identical. The biggest difference? James didn’t leave a team with no hope against the reigning conference heavyweights, the Boston Celtics, to play in the NBA-indifferent city of Miami. This time, he left the reigning conference heavyweights to go back to the team he left because they finally realized that putting good players around James was the best way to have him wear their uniform.
When LeBron left Cleveland, he was a 25-year-old who had already logged almost 20,000 minutes played during the regular season. Factoring in their playoff appearances, he’d spent 22,231 minutes in a Cavs uniform — over 370 hours, or 15 days and change, of high-level NBA action. As anyone who watched James during his formative years knows, a majority of it was spent going full bore. He’s played nearly 15,000 minutes of NBA basketball since then, and that’s before we get to the Olympic duties and the charity games and the rest of it. On top of the wear-and-tear that anyone picks up from being athletic, James will turn 30 this December, and 30 has a tendency to be a bad year for NBA athletes.
In 2009, when LeBron James was about to turn 25, The Wall Street Journal did some reporting on an interesting study on those who make basketball a profession. The lede then was a question, about whether or not is LeBron peaking right now (as in, at 25) which could (sort of) be inferred by the data, which suggested that NBA players tend to hit their highest individual ability around at age 25. This was largely sensationalist, because, as the study’s author noted, “the key issue is not the specific point in the player’s 20s where the peak occurs, but rather that performance after age 30 has a noticeable drop-off.” Now, of course, we’re in the year 2014, and LeBron James is about to pass that second, more noticeable, milestone.
Aging happens to everyone, and LeBron James is no exception. There will be one day when he can no longer play basketball at the highest level, and at some point he’ll retire. We all know this. What we can’t know is how quickly his game will drop off — and there’s no way of knowing whether he’ll wind up closer to John Stockton or Allen Iverson. The specifics may remain uncertain until we can examine his career in totality, but we can make some educated guesses and, assuming that James sticks close to his NBA peers, historically speaking, we can assign a bit of a prediction.
The original study was originally reported as a bit of promotion for Stumbling Upon Wins, which was published in 2010 and is now on Google Books. In the book, and reused in a blogpost by the authors with a wonderful title (“NBA Players Age Like Milk“), they provided a table for how they expect the average player’s Wins Produced — a catch-all metric that’s similar to, but more comprehensive than, things like PER — to change year in and year out. In 2010-2011, at the age of 26, James posted a WP/48 of 0.270. Crudely plugging that into the table from Stumbling Upon, that would mean that James would put up a WP/48 of roughly 0.195 next year — assuming he sticks close to the average NBA player, who posts a WP/48 at age 30 that is 71 percent of the one he posted at 26.
What does that mean for our hypothetical LeBron? In the vacuum, he’d still be twice as good as the average basketball player, but not nearly as impressive as his first year with the Heat. While that doesn’t feel right at first blush, because our first memory of LeBron is of the player who put up consistently similar numbers in each of his four years of his stay in Miami, remember that there’s only a projected variance of 10 percent between a player’s effectiveness before he hits 30. Now, of course, we can watch the games, keyed in to whether or not he’ll buck the trends and continue to play at the highest level. For anyone interested in doing the math themselves, you can find the formula for Wins Produced here, and all the relevant data at Basketball Reference.