Every ranking on MSquared Sports uses the same handful of adjustments. This page explains each one in plain language.
Player counting stats are scaled to 75 possessions instead of per game or per 36 minutes. That puts a fast 1980s team and a slow 2000s team on equal footing, and it stops a player from looking better or worse just because of how many minutes he played. 75 is close to the number of possessions a starter plays in a typical game.
Efficiency and team ratings are measured against the league average of that season. rTS is a player's true shooting percentage minus the league's. rOrtg and rDrtg are a team's offensive and defensive rating (points per 100 possessions) minus the league's. A plus five means the same thing in 1962 and in 2022: five points better than the league of that year.
For offense, higher is better. For defense, a lower (more negative) number means fewer points allowed than the league average, so lower is better. The Defenses tables are labeled that way.
In the playoffs every series is also graded against the opponent. aTS (adjusted true shooting) compares a player's efficiency with what that opponent normally allows. For teams, PS aOrtg is the same idea for offense, averaged across the series a team played. PS aDrtg is the defensive version: how far each opponent's offense fell below its regular-season norm, averaged across the team's series. A series against a great opponent counts for more than one against a weak one.
On Court shows the team's offensive and defensive rating relative to the opponent while a player was on the floor. rNet is their sum. It describes the team with that player playing, so it is not an on/off number.
Each team gets a regular-season figure (RS) and a playoff figure (PS). Average is the mean of the two. Sumsq is the square root of the sum of their squares, a combined score that rewards teams that were strong in both parts of the season instead of one. On the Offenses and Defenses pages the final ranks are the author's judgment informed by these numbers, so they can differ slightly from a pure Sumsq sort.
The one-year lists rank single seasons. The two- and three-year lists rank consecutive seasons by the same franchise, using the average of the yearly regular-season and playoff figures. Expanding a three-year run shows each individual season. Because the same franchise can peak more than once, a franchise can appear on a list more than once.
Steals and blocks were not tracked before 1974, so early rows leave those columns blank. Pace and opponent data are also missing for the Russell-era Celtics playoff series. Their playoff defense is estimated from the points they allowed per game against what each opponent normally scored. Those teams are listed separately and left unranked, because an estimate cannot be compared fairly with a modern team measured directly. They are included because their dominance and place in NBA history demand it.
Some seasons rest on only a few playoff games. Where the table offers a minutes filter, use it to hide thin samples before drawing conclusions.
All numbers and calculations are original to MSquared Sports. Some of the data used to calculate era, player and opponent adjustments is taken from Basketball-Reference.com. Team pages are updated through the 2026 playoffs.