If a higher point total was the sole culprit behind the higher average scoring margin, we鈥檇 expect a similar tale when looking at regular season data. But that鈥檚 not the case.
To test this theory, the average points per game in the regular season and the playoffs over the past seven years鈥攂ack to 2016, when fans first saw an increase in playoff blowouts鈥攚ere compared to that of the seven years prior, 2009-15.
Both the playoffs and the regular season increased their average scoring margin at a similar clip between those two time periods. The regular season鈥檚 points per game grew by 9.1% over the sampled seasons, and the playoffs鈥� points per game grew by 10%.
The same isn鈥檛 true for the average scoring margin. During the 2009-15 time frame, both the playoffs and the regular season averaged a scoring margin of 11. In the seven years that followed, however, the regular season鈥檚 average scoring margin increased 5.8% to 11.6 and the playoffs increased 17.3% to 12.9, growth spurts incongruous with the more consistent change in points per game totals.
So what happened? The home-court advantage might be playing a bigger role during the playoffs. Since the 2002-03 season, home teams have an average point differential of +4.3 in the playoffs, up 54% from +2.8 in the regular season. This difference in home-court advantage could be magnified when coupled with larger points per game totals.
The 2020 playoffs held in a COVID-19 bubble can be treated as a makeshift control group. That year every playoff game was played on a neutral court at Disney World, and, notably, it鈥檚 the only year of the past seven that didn鈥檛 reach the 12-point scoring margin watermark discussed earlier.
In fact, the 11.6 average scoring margin during the 2020 playoffs lines up nicely with the 11.6 average margin found during the regular season over the past seven seasons. Because neutral site games had lower scoring margins, there鈥檚 potential evidence that playoff home-court advantage is more crucial in a higher-scoring, 3-point-shot friendly NBA.
Ultimately, a slew of factors could impact the rise in playoff blowouts. The Warriors鈥� road beatdown of the Celtics to clinch the title in Boston anecdotally suggests that home-court advantage isn鈥檛 everything.
Beyond home-court advantage, other culprits may be more difficult to diagnose with data鈥攕uch as general player wear-and-tear throughout a long season or the effects of playoff travel鈥攁nd would require a deeper analysis.