The predictive power of the NBA's 20-game mark

On Monday night, the NBA passed the quarter mark of the 2021-22 regular season. Although there's nothing inherently magical about the 20-game mark, which the San Antonio Spurs will become the last team to reach it on Thursday, it is conveniently about the point where this season's results have historically become as predictive as our preseason expectations.

Already, some of the league's biggest early surprises have started to drift back toward the pack. After starting 10-3, the Washington Wizards have lost five of their past eight games. The defending champion Milwaukee Bucks, who started 6-8 as they battled absences for several starters, have caught the Wizards in the standings thanks to a seven-game winning streak.

Meanwhile, the top three in the Western Conference looks reasonably set with the Golden State Warriors, Phoenix Suns and Utah Jazz a level above anyone else in the middle-heavy West.

Nonetheless, the first month and a half of the new season has still provided enough time to change our opinions of a handful of teams.

Based on the predictive power of team stats at the same point in past seasons, let's look at the biggest movers thus far, including one early favorite that has seen its projection drop from their preseason total nearly twice as much as any other team in the league.

Predicting future wins in the NBA

First, let's look back on past 82-game seasons to see how quickly team performance stabilizes. Specifically, considering seasons from 2012-13 through 2018-19 (the last 82-game schedule prior to this one), I looked at how well a handful of measures explained what a team's record would be over the remainder of the year.