It is denoted as PER, and is derived by a very complex calculation designed to compensate for different teams' varying style of play, among other factors.
A PER of 15 is considered average across the entire league (not true of EFF), and serves as a simple benchmark against which any player may be quickly compared to indicate his approximate net worth to an NBA franchise.
[3] Teams intending to compete for the championship typically seek to enlist at least two star players with high efficiency ratings above the low twenties.
According to the modified PER formula used at Basketball-Reference.com,[4] the highest PER ever achieved over an entire single season in the NBA was 32.85 by Nikola Jokić in 2021–22.
In the 2021–22 NBA season, three players achieved this feat : Nikola Jokić (32.85), Giannis Antetokounmpo (32.05) and Joel Embiid (31.16).