Answering the big questions about the NBA's wild points binge

ByKEVIN PELTON
October 22, 2018, 9:46 AM

When the Atlanta Hawks (!) and Sacramento Kings (!!) topped 130 points on Sunday, it brought us to nine such games through the first six days of the 2018-19 season. As recently as 2012-13, there were just 14 such games through the entire season.

So far, teams are averaging 113.3 points per game, an increase of 7.0 from last season's 106.3. If maintained, that figure would blow away the previous high since the ABA-NBA merger of 110.8 PPG in 1984-85. To find a higher-scoring NBA season, you'd have to go all the way back to 1969-70 (116.7 PPG), when there were 14 teams and Atlanta played in the Western Division.

What explains the surge in scoring? Will it in fact continue? Let's try to answer the big questions about the big point totals we've seen in the season's first week.

What's driving the scoring: pace or efficiency?

So far, both the number of possessions per game and points scored per possession are up.

As compared to full-season totals from last year, pace has increased by 5.8 percent (from 99.6 possessions per 48 minutes to 105.4) and offensive rating by 1.2 percent (from 106.2 to 107.5).

How predictive are those metrics at this point of the season?

For the sake of comparison, I used Basketball-Reference.com's Play Index to look at stats through the first three games of past seasons for each team. (We're not quite to three games per team so far this season, but close -- the average through Sunday was 2.6 games per team.)

When it comes to leaguewide pace, the first three games are predictive of season-long results -- with a catch. While the final count of possessions per 48 minutes is typically relatively similar to what we see over the first three games, it has declined by 1.1 possessions on average. As compared with the first three games of last season, the jump in pace is just 3.6 percent, not quite as substantial a leap as using the full 2017-18 results would suggest.

Nonetheless, absent some kind of underlying change, the pace so far suggests the league is likely to play faster than at any time in recent history. Over the past decade, the biggest decline in pace from the first three games to the full season came in 2010-11 (3.0 fewer possessions). Even if we applied that large of a decline to the average from the first three games this season, that would still leave this season's pace as the NBA's highest in nearly three decades.

Conversely, it's well established that efficiency tends to start slowly and improve over the course of the season. And indeed, offensive rating has increased over the first three games every season over the past decade. That suggests we're in for even more efficient scoring than we've seen, which would already be the highest points per possession since turnovers were first tracked in 1973-74. (The previous high-water mark was 106.2 points per 100 possessions in 2016-17, with last season falling just short of that mark.) It also means that efficiency is up nearly as much as pace, a 3.4 percent increase compared with the first three games of 2017-18.

Ultimately, the combination of slower pace and better efficiency has tended to produce slightly higher scores as the season goes on. So the scoring we've seen so far in 2018-19 is probably not a fluke.

Do this year's rule changes explain higher scoring?

Perhaps. While there's been some thinking that the new rule resetting the shot clock to 14 after offensive rebounds rather than 24 is driving the pace increase, it's probably not a significant factor. Analysis by Daniel Massop on Nylon Calculus over the summer found that just 6 percent of offensive rebounds in 2017-18 resulted in a possession that took longer than 14 seconds -- about half an offensive rebound per team per game, not enough to substantially change pace of play.

More specifically, Mike Beuoy of Inpredictable.com -- which tracks offensive and defensive pace by seconds per possession -- posted on Twitter that while the average time of possessions involving offensive rebounds is in fact down by 0.7 seconds this season, the average time for possessions without an offensive rebound has decreased even more: 0.9 seconds per possession, on average, or a 6.5 percent decline. So teams are moving faster even when there's no need for them to do so because of the shot clock.

It's tougher to tell whether a change in the enforcement of the rules is a factor in terms of efficiency. As I detailed during the preseason, the NBA made enforcing rules limiting grabbing and holding away from the ball a point of education for referees and teams this year. League vice president and head of referee development and training Monty McCutchen promised those calls would continue into the regular season, and so far they have.

This season, referees have called an average of 23.6 fouls per 48 minutes, up from 21.6 in the first three games of 2017-18 and 19.7 over the full season. (Foul rates typically decline as the season goes on.) It's also clear the additional calls are primarily coming away from the ball. According to Second Spectrum tracking, 59 percent of fouls called so far this season have been non-shooting, as compared to 54 percent throughout 2017-18. That means non-shooting fouls are up by 3.3 per 48 minutes, whereas there have been just 0.6 more non-shooting fouls per 48 minutes.

While non-shooting fouls do put teams in the bonus earlier, they haven't translated to many more free throw attempts. Teams are making trips to the free throw line on 9.7 percent of possessions, which is up from 9.2 percent in the first three games last season and 8.7 percent over the full season. However, the rate is the same as it was in the first three games of 2016-17 and lower than that of seven of the previous eight seasons. So freedom of movement foul calls aren't directly responsible for much of the increase in efficiency.

Teams getting more attempts at the rim

More than free throw attempts, the single biggest driver of increased efficiency is better shooting. So far, teams are making 50.7 percent of their 2-point attempts and 36.3 percent of their 3s, both better than the accuracy over the first three games of any season from the past decade.

Accounting for the added value of 3s, that has produced an effective field goal percentage (eFG) of 52 percent, up from 50.8 percent through three games in 2017-18 (the first time in the past decade that it cracked 50 percent) and similar to the league's final 52.1 percent eFG last season -- the highest in NBA history, just ahead of 2016-17 and 2015-16. (You should be sensing a trend here.)

Teams are scoring more efficiently from the field as they improve their shot selection by trading long 2-pointers for 3s. Indeed, according to data from NBA Advanced Stats, the percentage of shots teams have taken as 2s outside the paint had declined from 19.1 percent last year to 15.7 percent through Saturday's games in 2018-19, which would be a new all-time low. (As recently as the post-lockout 2011-12 season, more than 30 percent of all shot attempts were 2-pointers from outside the paint.)

Intriguingly, not all of those long 2 attempts have become 3s this season. The rate of 3-point attempts is up more modestly from 33.7 percent of shots to 34.5 percent. Instead, most of the missing long 2s have turned into attempts in the restricted area around the basket, which are up from 31.7 percent of shot attempts to 33.9 percent -- which would be the highest rate in the 21 years for which the NBA has published shot-location data.

We might be seeing the effect of the NBA's emphasis on freedom of movement here. According to Second Spectrum data, the increase in shot attempts in the restricted area has come almost entirely on assisted shot attempts as compared to the first six days of the 2017-18 season -- up from 7.3 per 100 possessions early last season to 8.1 so far this season. That would be consistent with more scores on cuts to the basket.

That noted, there doesn't appear to be any singular explanation for why offense has suddenly leaped in the NBA. While freedom of movement probably has played a role, what we've seen through the first week of 2018-19 looks more like the product of long-term trends toward faster pace of play and more efficient shot selection. Scoring has risen five of the past six seasons, and while there has never been a year-over-year jump quite like we've seen so far -- the largest increase in points per game in the past 17 years was 3.8 PPG from 2003-04 to 2004-05 -- the high-scoring NBA looks like it's here to stay.