FIFA's 2020 Global Competitive Balance Report is at https://img.fifa.com/image/upload/uq7rwnxcj6m55frwmrhs.pdf and here are some statistics. This only includes the top level in each country. FIFA gave statistics about champions in the last five and last fifteen seasons. Canada, Montserrat, and Puerto Rico are included for the last five seasons and excluded for the last fifteen seasons due to a new league or interruption. 1. Amount of champions in the last five seasons out of 35 member associations (MAs): 1: 3 MAs which is 9 percent Canada (Forge FC, league existed for two seasons). Montserrat (Royal Montserrat Police Force, league was disrupted), and Puerto Rico (Metropolitan FA, league was disrupted) 2: 5 MAs which is 14 percent 3: 14 MAs which is 40 percent 4: 12 MAs which is 34 percent 5: 1 MA (Dominican Republic) which is 3 percent 2. Amount of champions in the last fifteen seasons out of 32 MAs: 2: 1 MA (British Virgin Islands) which is 3 percent 3: 3 MAs (Cayman Islands, Grenada, and Suriname) which is 9 percent 4: 5 MAs (Anguilla, Belize, Guyana, St. Vincent and the Grenadines, and US Virgin Islands) which is 16 percent 5: 6 MAs (Bahamas, Costa Rica, Guatemala, Honduras, Nicaragua, and St. Kitts and Nevis) which is 19 percent 6: 7 MAs (Antigua and Barbuda, Aruba, Barbados, Dominica, Dominican Republic, Jamaica, and Trinidad and Tobago) which is 22 percent 7: 5 MAs (Bermuda, Cuba, Curacao, El Salvador, and Panama) which is 16 percent 8: 1 MA (Mexico) which is 3 percent 9: 1 MA (Turks and Caicos Islands) which is 3 percent 10: 2 MAs (St. Lucia and USA) which is 6 percent 11. 1 MA (Haiti) which is 3 percent 3: Amount of titles by the most common champion in the last fifteen seasons out of 32 MAs: 10: 2 MAs (Nicaragua and Suriname) 9: 2 MAs (Belize and Cayman Islands) 8: None 7: 1 MA (British Virgin Islands) 6: 5 MAs (Aruba, Bahamas, Costa Rica, Guatemala, and Honduras) 5: 6 MAs (Anguilla, Barbados, Curacao, Guyana, Jamaica, and US Virgin Islands) 4: 12 MAs (Antigua and Bermuda, Bermuda, Cuba, Dominica, Dominican Republic, El Salvador, Grenada, Mexico, Panama, St. Kitts and Nevis, St. Vincent and the Grenadines, and Turks and Caicos Islands) 3: 4 MAs (Haiti, St. Lucia, Trinidad and Tobago, and USA) Having more champions means the most common champion will have fewer titles. 4. Longest title streak in the last fifteen seasons out of 33 MAs: 2: 17 MAs which is 52 percent 3: 10 MAs which is 30 percent 4: None 5: 4 MAs which is 12 percent 6. 2 MAs which is 6 percent 5. Longest active title streak out of 34 MAs: 1 (last two champions were different): 28 MAs which is 82 percent 2: 5 MAs which is 15 percent 3: 1 MA (Nicaragua's Real Esteli) which is 3 percent 6: Most titles Last five seasons: Suriname's Inter Moengotapoe with four Last fifteen seasons: Nicaragua's Real Esteli and Suriname's Inter Moengotapoe with ten 18 MAs (51 percent) had the most common champion in the last five seasons and the last fifteen seasons be the same club. Concacaf is much worse than UEFA, but at least Concacaf has more competitive leagues. In UEFA there have been long title streaks for elite clubs like Bayern Munich and Juventus, but also clubs outside the top twenty leagues in UEFA like Belarus's BATE Borisov and Moldova's Sheriff Tiraspol. 7. 26 MAs (74 percent) have a playoff. That is above CONMEBOL's 70 percent to be the highest percent of any confederation. The playoff winner has been the regular season first place club 46 percent of the time, second place club 26 percent of the time, third place club 14 percent of the time, and fourth place or lower club 14 percent of the time. Mexico has not had any of the last five regular season champions win the playoffs, and MLS has had one of the last five. Canada (only one season), Grenada, Mexico, Panama, Suriname, and US Virgin Islands have not had any of the last five regular season champions win the playoffs. Anguilla, Barbados, Guyana, and Puerto have had the regular season champion win the playoffs every time. 8. In the last five seasons, first place clubs have averaged 76 percent of the possible points, second place clubs have gotten 68 percent, and third place clubs have gotten 60 percent. 9. The points difference between first and second ranged for 0 once to 7 twice.
Thank you for sharing, that's some great info. The easiest way to create greater parity if desired would be to have a small playoff, like MLB used to have with a 4 team field. If you include more teams, like NBA and NHL does, it dilutes the value of league games and starts to resemble a cup competition too much. All the leagues with playoffs probably have more competitive balance. At the same time, soccer fans simply don't seem to value league titles as much as fans of the four major American sports since each domestic league around the world is essentially a means to an end for an international club competition rather than an end in itself (either for Champions League/Libertadores or Europa League/CAF Cup/AFC Cup/Copa Sudamericana). For example, Dinamo Zagreb's win over Tottenham was probably viewed by their supporters as a bigger achievement than winning a league title. As far as supporters of other Croatian clubs, they probably cheer for D. Zagreb in international competition and tolerate their dominance for the sake of national pride. Additionally, cup competitions and relegation battles make soccer leagues much more compelling than just the battle at the top of the league.