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Which teams were better: Tom Brady’s New England Patriots or Bill Russell’s Boston Celtics? Which GOAT’s squads were more dominant: Michael Jordan’s Chicago Bulls or Wayne Gretzky’s Edmonton Oilers?
These are, of course, unanswerable questions, but sports fans are unable to resist them. It’s just part of any die-hard dialogue, debating these age-old questions: What’s the greatest team within each sport? And which team overall is the best of all time? With more than a century of records to lean on for some professional leagues, this question may seem vast and daunting. However, we gathered and analyzed these statistics to identify the best dynasties across the four major U.S. sports leagues (NFL, MLB, NBA and NHL).
When deciding how to rate dynasties, we chose to emphasize two factors: regular season dominance and playoff performance.
To measure regular season dominance, we gathered standings data for each team across the four major North American sports leagues. We then took the Z-score of each team’s winning percentage that season to determine how dominant they were. Unlike straight win-loss records, Z-scores represent how far above average a team is in comparison to their opponents within their year, giving a better look at a team’s dominance compared to their peers.
For example, two teams could both go 14-2, but one could do so in a year in which most other teams went 8-8, while the other could do so in a year when half of the teams also went 14-2. By using Z-scores, we are able to rate the first team higher, since its performance stood out more above the competition.
To measure postseason performance, we assigned “dynasty points” with the following weights:
While these weights are subjective, we tried to balance between rewarding champions and ensuring that teams that lost out in a close final game weren’t penalized too harshly.
Then, we took a rolling average for five-year and 10-year intervals for both regular season and postseason performance. (We also did calculations for three-year and 15-year intervals, which can be found here.) Finally, we rescaled the data across sports to put each team on a 0-100 scale and added up the regular and postseason scores to arrive at our final “dynasty score.”
Overall scores range from 0 to 200, with a maximum of 100 points coming from each regular and postseason performance.
The 2014-18 Golden State Warriors take the top spot here. Stephen Curry and company only won three titles, but they reached two other finals and dominated the regular season. In fact, the Warriors’ performance ranks as the top five-year regular season stretch of any team across the Big Four sports leagues (as denoted by their 100 out of 100 regular season score).
Following the Warriors are the only four teams to win five straight titles. What stands out about these teams is that they all played in roughly the same era—one with an extreme lack of parity. Without free agency, there was little player movement, allowing teams to stockpile talent and never let go. As a result, the 1950s was one of the low points of parity in MLB; only three teams won Stanley Cups between the end of World War II and 1960, and the Cleveland Browns were so dominant that the new All-American Football Conference (AAFC) collapsed after Cleveland’s fourth-straight title.
Some could argue that this diminishes the magnificence of these dynasties, saying they should not be ranked so highly because of their easier path to titles. While these are valid concerns, we chose to use only on-field performance, rather than make adjustments that could stack the deck the other way. Once again, though, this makes the Warriors’ perch atop the rankings even more impressive. They were able to dominate with a (mostly) homegrown roster, even in an era with protections for weaker teams like salary caps and drafts.
The Boston Celtics were special in the 1950s and 1960s. They won a record nine titles in 10 seasons, including eight straight. However, the Celtics weren’t a team that only got hot come playoff time. Boston was also one of the greatest regular season teams ever, with only the 1990s Atlanta Braves, 2000s Detroit Red Wings and 1970-80s Montreal Canadiens performing better in comparison to their peers. As a result of their all-around excellence, the 1956-1965 Boston Celtics rank as the best dynasty in any of the four timeframes we examined, with a grand total of 196.1 points out of 200.
After the Celtics are the aforementioned Browns, who maintained their excellence even after dismantling the AAFC, reaching the title game in each of their first six NFL seasons. Outside of the Browns, though, almost all of the top teams come from big markets. Three New York Yankees teams rank in the top 10, while the next-best NBA teams come from Los Angeles and Chicago. Given the “big-market effect,” in which teams from bigger cities can get more revenue from ticket sales and local TV deals than teams from smaller cities, it’s no surprise that the best dynasties come from major metropolises. Therefore, when a small-market team, such as the 16th-ranked San Antonio Spurs, is able to reel off sustained success, its accomplishments are all the more impressive.
A couple of notable teams missed the 10-year rankings. First, while the New England Patriots put together an outstanding run of dominance in the 2000s, their (relatively) poor performance around 2010 cut the overall dynasty in half, and the Patriots’ best 10-year run finished only 14th in our rankings. Additionally, there is no “100” regular season score in the top 10, indicating that the best regular season dynasty did not make it. While the Atlanta Braves reeled off 11 division titles in a row (14 if the strike-shortened 1994 season is excluded), they struggled mightily in the playoffs. Since Atlanta only won one World Series in their nine postseason trips between 1991 and 2000, they only finished 12th in the dynasty rankings.
Everyone has a different definition of a dynasty. Some people look for the highest peak, while others search for long-term consistency. Some people say that a team can’t be a dynasty without a certain number of titles. Others believe that greatness is more than just rings. Since defining dynasties is so subjective, we’ve tried to take a more holistic perspective, combining regular season and postseason performance and including all teams, regardless of era or sport. Therefore, our analysis can serve as a foundation to enable fans to draw their own conclusions, and then make adjustments based on what they value. We hope we have settled some cross-sport, cross-town and cross-generational arguments (and maybe started some new ones, too).