The NFL is unlike any other league in that teams can make quick turnarounds from year to year, both positively and negatively. Going from “first to worst” or “worst to first” is not unusual, and unlike the NBA or NHL, in some seasons more than half the teams that qualify for the playoffs are different from the previous year. I believe this parity contributes to the league’s popularity. Although exceptions exist, such as New England’s long run of success, franchises aren’t typically fixed in long eras of winning or losing.
So it benefits the bettor greatly to know which traits lead teams to improve or decline quickly. Which stats are key to finding vulnerable teams that could fall off? What is the typical resume of a team that improves greatly from one season to the next? Those who can find the answers can take advantage of not only the season win totals but also the point spreads in the early weeks of the season before oddsmakers catch up.
I consider it a rite of spring to go through the statistical traits I believe are most important in determining which NFL teams have the best chance of getting better or worse and by how much. Among the things I look at are turnover statistics, offensive or defensive production not in line with won-lost records, number of close wins or losses, and trending records from multiple seasons. Of these, turnover statistics usually are the most influential, so I use them in many of the following systems.
Read through the findings and make your own assessments of which teams might not be what we saw in 2019.
Systems of teams that had negative turnover differentials the previous season
— Fourteen of 15 teams since 2010 that had turnover differentials of -16 or worse and did not make the playoffs improved the next season. The only one that didn’t maintained its 5-11 mark: the Jets from 2016 to ’17. San Francisco and Tampa Bay qualified last year and improved by nine and two regular-season wins. The average regular-season win improvement was 4.9 wins per season.
Teams affected in 2020: L.A. Chargers, N.Y. Giants
— Since 2009, 33 teams had negative turnover differentials and won fewer than six games against the spread. All but two improved their ATS winning percentage the next season, by an average of 19%. All but five improved their outright winning percentage as well, by an average of 19%, and eight qualified for the playoffs.
Teams affected in 2020: L.A. Chargers, Cleveland
— Fourteen teams since 2009 had negative or even turnover differentials yet still won double-digit games against the spread. Eight reached the postseason the next year.
Team affected in 2020: L.A. Rams
— Of the 23 teams that improved their won-lost percentage by 34% or more from one season to the next since ’09, all but four had negative or even turnover differentials the previous season.
Teams potentially affected in 2020: Arizona, Atlanta, Carolina, Cincinnati, Cleveland, Dallas, Detroit, Jacksonville, L.A. Chargers, Miami, N.Y. Giants, N.Y. Jets, Oakland, Philadelphia, Tampa Bay
Systems of teams that had positive turnover differentials the previous season
— Only three of the 13 teams since 2009 that had turnover differentials of + 1 or better per game improved their records the next season. The average won-lost percentage decline was 9% (8% ATS), or about two wins per season.
Team affected in 2020: New England
— Teams that had positive turnover differentials and won 10 or more games against the spread are fade teams the next season. Of these 63 teams since 2009, 45 had won-lost records that declined by an average of 11.5% outright and 14% against the spread. Furthermore, of the 58 that reached the playoffs, 25 failed to do so the next season.
Teams affected in 2020: Baltimore, Buffalo, Green Bay, Kansas City, New Orleans, San Francisco, Tennessee
— Since 2009, 35 teams had turnover differentials of + 5 or better and failed to reach the postseason. Only 10 reached the postseason the next year, and only 13 improved their records. These are typically play-against teams, as failing to reach the playoffs does not provide momentum for the next season.
Team affected in 2020: Pittsburgh
— Only four of the last 27 teams that had positive turnover differentials and won seven or fewer games against the spread reached the playoffs the next season, and only 10 improved.
Teams affected in 2020: Indianapolis, Pittsburgh, Washington
— Of the 12 teams whose ATS won-lost percentage declined by 31% or more from one season to the next since ’09, all had positive turnover differentials of + 4 or better the previous season.
Teams potentially affected in 2020: Baltimore, Buffalo, Green Bay, Kansas City, Minnesota, New England, New Orleans, Pittsburgh, San Francisco, Seattle, Tennessee
Systems of teams whose offensive or defensive production or point-differential stats the previous season didn’t accurately reflect their won-lost records
— Since 2002, 10 teams won 10 or more games despite scoring 20 or fewer points per game in a season. The next year, six dropped by at least six games in the win column, and the average drop was 3.6 wins per year.
Team affected in 2020: Buffalo
— Fairly steady season-to-season improvement has been made from the group of teams that have won six or fewer games despite scoring 22+ PPG. Since 2000, only three of the 24 teams were worse the next season, and the average win improvement was 2.45 per season.
Team affected in 2020: Arizona
— Since ’96, 20 teams have somehow won six or fewer games despite allowing 20 or fewer points per game in a season. In the next season, nearly half improved by at least four wins, and the average improvement was 2.15 wins per year.
Team affected in 2020: None (Denver was closest at 7-9)
— A consistent season-to-season decline has been made by teams that have won 10 or more games despite allowing 22+ PPG. Over the last 20 seasons, only two of the 27 teams were better the next season, and the average drop in wins was 2.92 per season.
Teams affected in 2020: Houston, Seattle
— Tampa Bay’s 458 points last season were the seventh most scored in the last 28 seasons by a team that did not make the playoffs. The other six: the 2004 Chiefs (483), the 2014 Eagles (474), the 2016 Saints (469), the 2002 Chiefs (467), the 2008 Saints (463) and the 2012 Saints (461). The combined record of those teams the next season was 67-29, good for 69.8% and an average of 11.1 wins per season. Only one failed to make the playoffs, and one other, the 2009 Saints, won the Super Bowl.
Team affected for 2020: Tampa Bay
— If you examine positive point differentials with losing records, the last 13 teams that had this combination improved their records the next season, including the 2017 Super Bowl champion Eagles. The average win total for these teams was 9.9, with seven winning at least 11 games, and the average win improvement was 3.2 per season.
Team affected for 2020: Tampa Bay
— When considering negative point differentials with 8-8 or better records, only four of the last 22 teams to achieve this dubious honor improved the next year. The average drop was a minimal -1.5 wins per season, but the margin of making the playoffs for teams like this was already small.
Teams affected in 2020: Chicago, Houston, Pittsburgh
Systems of teams that had unusually high or low totals of close wins the previous season
— Seattle’s 10 “close wins” — eight or fewer points — last year were the most by any team over the last 28 seasons. In that span, the 28 teams with eight or more close wins combined for an average decline of 3.1 wins per season.
Teams affected in 2020: Green Bay, Houston, Seattle
— The last three seasons have trended against teams that win a lot of close games. Included in that span have been 27 teams that won six or more games by eight or fewer points. Only one has improved the next season, with an average drop of 2.96 wins per year.
Teams affected in 2020: Chicago, Green Bay, Houston, Las Vegas, New Orleans, Pittsburgh, Seattle
Systems of teams that had unusually high or low totals of close losses the previous season
— Since ’98, 27 teams have lost eight or more games by eight or fewer points. Their combined average improvement the next season was a hefty 3.96 wins, with 25 improving.
Teams affected in 2020: Cincinnati, Detroit, L.A. Chargers
— Since 2008, 54 teams went into the next season after having lost at least six games by eight or fewer points. Of these, 44 improved their won-lost records the next season, including 25 by four or more wins. The average improvement was 3.1 wins.
Teams affected in 2020: Carolina, Cincinnati, Dallas, Detroit, Indianapolis, L.A. Chargers, Tampa Bay
Systems of teams that had unusually high or low totals of blowout wins the previous season
— The last team to record at least nine double-digit wins in a season and improve its won-lost record the next year was Denver from ’97 to ’98. Since then, the average win decline of the 28 teams that did it was -4.1.
Team affected in 2020: Baltimore
— Seven teams over the last 25 seasons have won six or more games, but none by double digits. None improved the next year, falling by an average of 2.7 wins per season.
Teams affected in 2020: Las Vegas
Systems of teams that had unusually high or low totals of blowout losses the previous season
— In the last 21 seasons, only two teams have gone 8-8 or worse and suffered zero blowout losses of 20 points or more. Both won at least four more games the next season.
Teams affected in 2020: Dallas, Tampa Bay
— As another key sign of how teams can quickly improve from dreadful seasons, over the last 20 years, 31 teams have lost at least nine games by double digits. Of those, 26 improved the next season, and by an average of 4.0 wins per year.
Teams affected in 2020: Washington, Miami
— Since ’98, eight double-digit-win teams suffered all their losses by double-digit margins. Those teams dropped dramatically the next season, by an average of 5.25 wins per season.
Teams affected in 2020: None
Systems of teams based on their playoff results from the previous season
— Only two of the last 26 teams that lost in the Super Bowl improved their won-lost records the next season, with an average win decline of 3.3. Those with seven or more double-digit wins in the Super Bowl-losing season declined by an average of 3.8 wins.
Team affected in 2020: San Francisco
— Alternatively, the last 27 teams that won the Super Bowl were far better off in maintaining success, with only a 1.3-win decline per season, boasting an average won-lost record of 10.7-5.3. Only two of those 27 teams finished under .500 the next season. The most dominant of those teams, those outscoring opponents by 140 or more points, had an average won-lost record of 11.0-5.0 the next season.
Team affected in 2020: Kansas City
— No team in the last 28 years that went 13-3 or better and failed to make the Super Bowl improved its won-lost record the next season, and only two equaled it. The average win decline was 4.15 per season.
Teams affected in 2020: Baltimore, New Orleans, Green Bay
Systems of teams whose won-lost records are trending
— All 10 teams since 2000 that had won fewer games than the previous season in three straight years have improved their won-lost records, by an average of 4.8 wins per season.
Teams affected in 2020: None
— Since 2002, only one of the 13 teams that improved their records in three straight seasons continued that trend. The average drop was 3.7 wins, and the average record was 6.8-9.2.
Team affected in 2020: Baltimore
— All 12 teams since 2005 that won seven or more games fewer than the previous season rebounded to improve their won-lost records the next year, by an average of 4.75 wins.
Team affected in 2020: L.A. Chargers
— It’s not quite as dramatic as the previous item, but only one of the last 24 teams since ’98 that won seven-plus more games than the previous season improved the next year, with an average season win drop of 3.7.
Teams affected in 2020: Green Bay, San Francisco
Combination systems using the statistical characteristics detailed already
— Six teams have gone 7-9 or worse in a season despite positive turnover and scoring differentials, and five have made the playoffs the next season, improving by an average of 4.2 wins per season.
Teams affected in 2020: No teams qualify for this in 2020. Indianapolis was closest, with a 7-9 record, + 2 TO differential and -0.8 PPG scoring differential.
— Seven of the last nine teams that had negative turnover differentials but positive score differentials and didn’t make the playoffs did so the next season, including Tennessee in 2019.
Teams affected in 2020: Dallas, Philadelphia, Tampa Bay
— Only four of the last 31 teams that had positive turnover differentials but negative score differentials qualified for the playoffs the next season. Teams were 0-for-8 on this in 2019.
Teams affected in 2020: Denver, Indianapolis, Pittsburgh, Washington
— All but two of the 20 teams since 2009 that had negative turnover differentials and were outscored by more than 10 PPG improved their won-lost record the next season, by an average of 25%, or 3.95 wins per team. Four made the playoffs, and 11 improved by four or more wins.
Team affected in 2020: Miami
— Only six of the 29 teams since 2009 that had positive turnover differentials and outscored opponents by more than 8.0 PPG improved their won-lost records the next season. The average won-lost percentage decline was 10% SU and ATS, or about 2.5 wins per season.
Teams affected in 2020: Baltimore, Kansas City, New England, San Francisco