In terms of the game's hallowed numbers, it doesn't quite resonate like, let's say, 50.4 -- Wilt Chamberlain's historic scoring average in 1961-62 -- or Oscar Robertson's 30-12-11 triple-double that same season.
But it's a big one at Hollinger HQ, anyway. That 31.89 mark is Michael Jordan's PER (player efficiency rating) from the 1987-88 season, the top mark for any season since the league started tracking individual turnovers in 1973-74. (We don't have enough information for seasons prior to that, unfortunately, so we can't properly evaluate Wilt or the Big O.)
And it's an important figure at the moment because it's under assault this season from LeBron James.
That James is playing well is hardly a secret -- virtually every writer in the country has him either first or second on the MVP ballot heading into the season's final stretch. But the vagaries of the game's stats have made it difficult to appreciate what a historically great season he's having.
James doesn't lead the league in a single individual category, and his scoring and rebounding numbers are both down from a year ago. Yet when one looks at his accomplishments in total, and adjusts for both his minutes and his team's pace, he's having one of the greatest seasons in league history.
On a per-minute basis, he's averaging more points, rebounds, assists, blocks and steals than he did last season -- when he already was having a sensational season that included the league's best PER -- and is shooting better from the field, from the line and from 3-point range. Somehow, he's averaging fewer turnovers, too.
Add it all up and James' 31.69 PER through Sunday's games isn't only the best in the league, holding off a stern late charge by Miami's Dwyane Wade -- it's second only to Jordan in the past 35 years, and if James has a strong closing finish, it could end up as the best.
Even if he fails to match Jordan's all-time mark, he's already on hallowed ground. While Jordan's PER exceeded 31.0 on four different occasions, no other player in history had done it until James this season.
Nonetheless, the historic nature of James' campaign hasn't received nearly enough attention. His averages of 28.6 points, 7.6 rebounds and 7.3 assists are impressive, all right, but they don't look all that different from other seasons of recent vintage -- James' 30.0, 7.9 and 7.2 from a season earlier, for instance, or Larry Bird's 28.7, 10.6 and 6.5 in 1984-85, or Kobe Bryant's 35.4 points per game in 2005-06.
And on pure per-game totals, they pale beside Jordan's 32.5, 8.0 and 8.0 in 1988-89 ... let alone the Big O's triple-double in 1961-62.
TOP ALL-TIME PER SEASONS
But that's one of the reasons I created PER -- it enables us to make comparisons between seasons much more easily than we could do otherwise, because it scales to the same league average each season (15.0) and automatically adjusts for factors like pace, minutes, and whether offense or defense was ascendant at the time.
Unfortunately for James, he plays in one of the slowest-paced eras in the league's history. Though things have picked up a bit the past few seasons, even run-and-gun teams like Golden State and Phoenix would be considered walk-it-up outfits if they played in the 1980s or '90s. Jordan's 1987-88 Bulls, for instance, were the league's slowest-paced team at a pace factor of 98.2 -- one that would rank fourth from the top in 2008-09, just ahead of the fabled Suns.
The comparisons get even more lopsided once you go further back in history -- when Chamberlain averaged his 50.4 points, for instance, the Celtics were the only team to give up fewer than 116 points per game.
Just for fun, then, I decided to convert everyone's numbers into the same terms as Jordan's 1987-88 season, just so we could have an apples-to-apples comparison of some of the league's greatest seasons in the "triple crown' categories of points, rebounds and assists; as a guidepost, I also included each players' minutes per game and PER.
Historic seasons: Per-40-Minute stats at Chicago's 1987-88 Pace
As the chart shows, putting LeBron's current campaign at the pace of the 1987-88 season and pushing him back up to 40 minutes produces some extraordinary numbers -- on a per-possession basis, he's actually scoring nearly as much as Jordan did, with far superior ancillary numbers.
And if you want to go further back in history, check out what James' numbers would be if he was playing at the pace Robertson did back in 1961-62 -- we don't have exact figures because the NBA didn't keep very detailed numbers back then, but based on the shot data alone it would be in the range of a jaw-dropping 40, 10 and 10, as Neal Paine of Basketball-Reference.com found when he crunched the numbers.
Of course, pace is just one aspect of the comparison. We also have to deal with minutes, and this is one area where James falls short of his peers, believe it or not. Jordan averaged 40.4 minutes per game in 1987-88, and Bird played 39.5 in 1984-85; at the extreme end, Chamberlain played virtually every second of every game in 1961-62 -- because of games going to OT, he actually averaged 48.5 minutes per game that season.
This is partly because of how many blowout wins James' Cavs have had, but it's mostly a reflection of his era -- James' total, low as it seems in the chart, is actually fifth in the NBA this season. Teams have begun emulating the San Antonio Spurs' style of not overloading their best players with minutes and keeping them fresh for the postseason -- in fact, not one player averages as many as 40 minutes per game, an unthinkable state of affairs as recently as half a decade ago.
Unfortunately for James, it's another area where his numbers take a hit in historical comparisons. A season of 28.6, 7.6 and 7.3 sounds decent. A season of 30.3, 8.1 and 7.7 -- which is what his numbers extrapolate to if he played as many minutes as Jordan did in 1987-88 -- sounds downright amazing. And a season of 32.5, 8.7 and 8.3 -- which is what his numbers extrapolate to at the same pace and the same minutes -- is mind-blowing.
Back to PER for a moment. You can argue about whether James is having the greatest individual season ever -- to seal the deal, presumably it would have to be capped by a title, for starters, and there are a variety of subjective criteria one can add to the discussion that goes far beyond the limits of PER.
What's very clear, however, is that LeBron's campaign belongs on the short list. Few players in history have had a season approaching this one, and as of today only one player has exceeded it.
And James still has a shot at breaking the mark. I'm estimating James will play 270 more minutes this season, based on the Playoff Odds' current guess that Cleveland won't clinch home court throughout the playoffs until the final day of the season. If so, James would need a PER of roughly 33.0 for the remainder of the season to surpass Jordan during the Cavs' final dozen games -- a feat that is difficult but hardly impossible.
So while it may not have the panache of a hitter's chasing .400 or an NFL player's setting a new rushing record, the chase is on.
The conventional wisdom is that James is having a great season, but the reality is much deeper -- he's having what is arguably the greatest individual season in history, and it's time we gave him his due for it.
John Hollinger writes for ESPN Insider. To e-mail him, click here.