All Ratings
CBI

Competitive Balance Index

Measures league parity within an era. Lower concentration of championships and more varied playoff teams indicates higher competitive balance.

Formula

100 - (Championship Concentration x 30) + (Playoff Team Variance x 25) + (Win Distribution Evenness x 25) + (Unique Finalists x 20)

Championship Concentrationera_championship_concentration (30%)
Unique Playoff Teamsera_unique_playoff_teams (25%)
Win Distribution Evennessera_win_distribution_evenness (25%)
Unique Finalistsera_unique_finalists (20%)

Grade Scale

A+
72
A
70
A-
68
B+
62
B
57
B-
52
C+
42
C
0

Benchmarks

Small Ball Era72.6
Jordan Era 1990s72
2000s Post-Jordan Era71.9
1990s Bulls Dynasty70.7
Stern Era 1984-201458.3
Data Sources
Basketball-Reference.comNBA.com/stats

Grade Interpretations

A+

Historic cultural and business impact that transformed basketball into a global phenomenon.

A

Elite cultural/business impact with significant influence on media, commerce, and fan culture.

A-

Outstanding cultural/business impact with meaningful contributions to basketball's growth.

B+

Strong cultural/business impact with notable commercial or cultural milestones.

B

Above-average cultural/business impact reflecting meaningful era contributions.

B-

Moderate cultural/business impact reflecting some commercial significance.

C+

Below-average cultural/business impact with limited broader influence.

C

Minimal cultural/business impact reflecting a less commercially significant period.

Competitive Balance Index Leaderboard

#EntityScoreGrade
Small Ball Eraera72.6
A+
Jordan Era 1990sera72.0
A+
2000s Post-Jordan Eraera71.9
A
42020s International Eraera71.0
A
51990s Bulls Dynastyera70.7
A
6Larry Bird Magic Johnson Eraera69.5
A-
7Shaq Kobe Lakers Dynastyera69.5
A-
8Warriors Dynasty 2010sera68.9
A-
91980s Showtimeera68.9
A-
101970s ABA Merger Eraera68.4
A-
11Bad Boys Pistons Eraera67.5
B+
122010s Superteam Eraera66.9
B+
13Load Management Eraera65.5
B+
14Hand-Checking Eraera64.5
B+
15Expansion Era 1970sera60.9
B
16Bubble Era 2020era58.6
B
17Stern Era 1984-2014era58.3
B
181960s Celtics Dynastyera57.8
B
19Pre-Three-Point Eraera57.5
B
20Silver Era 2014-Presentera56.8
B-
21Bill Russell Dynasty Eraera56.8
B-
22Big Three Celtics Eraera56.3
B-
23Player Empowerment Eraera55.6
B-
24Seven Seconds or Less Eraera53.7
B-
25Lob City Clippers Eraera53.4
B-
261950s NBAera53.1
B-
27Heatles Eraera51.9
C+
28Grit and Grind Grizzlies Eraera51.6
C+
29Allen Iverson Culture Eraera49.7
C+
30Kareem Skyhook Eraera49.0
C+
31LeBron Era 2010sera42.9
C+
32Superteam Eraera41.1
C
33Warriors Splash Bros Eraera40.9
C
34Integration Era 1950sera32.1
C
35George Mikan Eraera31.0
C
36Pre-Shot Clock Eraera30.4
C
37Wilt Chamberlain Scoring Eraera28.3
C