With a month-and-a-half to go before NBA free agency, we have plenty of time to spend analyzing the decisions that are currently looming for the Sixers. At the top of the list of priorities is determining how to proceed with Tobias Harris and Jimmy Butler.

We know that both players will have a number of teams vying for their services, and that both players’ representatives will head into the market angling for a max deal, with the Sixers able to offer one more year of total guarantees and 3 percent more in annual raises than the rest of the market.

Butler was unquestionably the better player for the Sixers this postseason. But while he possesses a skill set that is definitively more well-rounded (particularly in the areas of defense and ballhandling), and while he might be a surer bet to land a max deal, there’s an argument to be made that Harris’ contract will come with much less risk attached than Butler’s (in fact, you may have read that argument recently).

Butler is three years older than Harris, with lots more tread on the tires. While Harris has improved his game in each of his seasons in the NBA, Butler is more or less a finished product, one who does not bring with him the sort of three-point-shooting prowess you’d like out of a high-dollar perimeter player in today’s NBA. That makes him a less-than-ideal fit with Ben Simmons and Joel Embiid, particularly Simmons.

As we saw throughout the postseason, he is a different player when he has the ball in his hands and is free to dictate. Add to that the way his tenures with the Bulls and Timberwolves soured, and there is plenty of risk involved even before you get to the health risk.

But what, exactly, is that risk? Studies suggest that, by the time a player is 30, which Butler will be in the first year of his new deal, he is well into the decline phase of his career. The aging curve goes something like this: improvement until 25 or 26, peak around 27, and then a decline that picks up speed with each year.

So what does that mean within the context of the four or five NBA seasons that Butler’s next deal will cover?

LeBron James leads the way in win shares no matter which age bracket he's in.
Rick Scuteri / AP
LeBron James leads the way in win shares no matter which age bracket he's in.

To answer that, it might make some sense to take a look at how players like him have aged in the recent past. To do this, we can look at players who have previously produced at a similar level during the ages of 26 and 29, and we can compare those four years of production with the four between the ages of 30 and 33, which are the years that would be covered by the maximum contract that the 29 other teams in the NBA can offer him. For mostly arbitrary reasons, let’s ignore the fact that the Sixers can offer him a fifth year.

If we limit our sample to the last 20 years, and to players who totaled at least 33 win shares between the ages of 26 and 29, and if we eliminate all of the players who are currently younger than 33, that leaves us with 25 players. That’s a nice square number, and Butler’s 37.1 win shares rests right around the median of the group.

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As you can see on the chart, LeBron James’ win shares are tops among our group of players in the 26-29 age range and the 30-33 age range.

Let’s take a look at the numbers to see how Butler compares.

First thing to note: among that group, the only player who did not play all four seasons between the ages of 30 and 33 was Chris Bosh, because of a heart condition that forced him to retire.

Second thing to note: Besides Bosh, only two players saw their minutes total decrease by more than 30 percent between the two time periods. Rashard Lewis logged 11,000-plus minutes between 26 and 29 years old and less than 6,000 between 30 and 33. Joakim Noah saw his minutes drop by nearly 75 percent between the two time periods.

Of the 25 players in the sample, 22 averaged at least 29 minutes per game between the ages of 30 and 33. Only five of the 25 averaged fewer than 60 games per season.

In other words, the vast majority of these players were on the court and contributing to an NBA rotation throughout the duration of the four-year period that Butler is about to enter.

Other notes:

  • 16 of 25 averaged at least 17 points per game.
  • 20 of 25 averaged at least 32 minutes per game.
  • Only 5 of 25 saw their true shooting percentage decline by more than 5 percent of what it was in the four years prior.

To sum all of this up, we can say that, historically, the bust rate for a player of Butler’s caliber has been very low between the ages of 30 and 33. There are very few lemons in this bunch.

That’s not to say that the Sixers should not expect a decline in Butler’s production. The players in our sample saw their production decline by at least 12 percent in most of the major statistical categories on a per-game basis between the ages of 30 and 33. More significant, they saw their win shares decline by 30 percent.

Now, win shares is a bit of an arbitrary standard by which to measure things. If you expand the sample to include players who totaled 20-plus win shares between the ages of 26 and 29, you suddenly must account for players such as Stephon Marbury, and Shareef Abudr-Rahim, and Deron Williams, and Michael Redd, and Baron Davis, all of whom were shadows of themselves or out of the league entirely by the age of 32.

Yet even when you expand the sample, the results are largely the same. Between 2000 and 15, 81 players totaled at least 10 win shares between the ages of 26 and 29. Sixteen played fewer than four full seasons between 30 and 33. But on a per-game basis, win shares were down 21 percent, minutes down 13 percent, points down 20 percent.

On the one hand, it’s a significant change. On the other, the vast majority of starting-caliber players are still productive members of NBA rotations at the age of 33. From Kobe Bryant and Dwyane Wade to Steve Nash and Chris Paul, there are tons of examples of players whose elite playmaking days extended into their mid-30s. There’s no questioning Butler’s dedication to his health and physical fitness.

On the other hand, one might argue that Butler’s lack of a consistent three-point shot and catch-and-shoot ability makes him especially reliant on his raw athleticism, which, according to the conventional physiological wisdom, is already in the process of diminishing, even if it does not yet manifest itself on the basketball court.

There’s no question Butler’s age offers more risk than Harris'. Enough to impact the Sixers’ desire to retain him? Time will tell.