With the NFL draft approaching next week, bettors are ramping up their preparation to take on all the offseason futures wagering options available in the market. Within the last week, win totals for all teams were released by books such as William Hill and BetMGM. Oddsmakers appeared to make no obvious misses, which would have been immediately attacked hard and then modified. One of the best ways to gain an advantage over the house on these options is to use stats from the previous season that have historically been very reliable for predicting which teams are due to improve or decline. Last week I analyzed the impact of tight or blowout wins and losses on a team’s prospects the next season. This is the second half of the series on changeover systems.
Last week I reminded readers how powerful this type of analysis can be. As proof, I predicted Tampa Bay would be a potential breakout team at this point last year. The NFL is unlike any other league in that teams can make quick turnarounds from year to year, positively or negatively. And unlike the NBA or NHL, more than half the teams that qualify for the playoffs one season are often different from the previous campaign. I believe this parity contributes to the league’s popularity. Furthermore, I reasoned last week on VSiN’s “The Lombardi Line” that three C’s can factor into this sudden change. The first is coaching, either from a change to a new guy or from improvement by the incumbent. The second is confidence, which can quickly transform after a solid offseason or first couple of good regular-season games. The third is cohesiveness, which can be affected quickly with the addition or departure of certain personnel.
Of course, certain statistical indicators a team exhibits in one season can illustrate how close it is to changing the status of those three C’s and, eventually, its fortunes the next season. Read through these findings, combine them with what we learned a week ago, add free-agent transactions and draft results — and then head to the betting window.
Systems of teams that had a negative turnover differential the previous season
— Sixteen of 17 teams since 2010 that had a turnover differential of -1.0 per game or worse and did not make the playoffs improved the next season. The only one that didn’t, the Jets, maintained their 5-11 mark from 2016 to ’17. The Chargers and Giants qualified on this system last year, and both improved by two wins. The average regular-season win improvement was 4.6.
Team affected in 2021: Denver.
— Since 2009, a total of 33 teams have had a negative turnover differential and won fewer than six games against the spread. All but two of those teams 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 20%. And nine qualified for the playoffs, including the Browns last season.
Teams affected in 2021: Dallas, Houston, Philadelphia.
— Fifteen teams since 2009 have had negative or even turnover differential yet still managed to win double-digit games against the spread. Nine of those teams reached the postseason the next year, including the Rams of 2020, who won a wild-card contest before falling in the divisional round.
Teams affected in 2021: None.
— 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 2021: Chicago, Cincinnati, Dallas, Denver, Detroit, Houston, Jacksonville, Los Angeles Rams, Las Vegas, Minnesota, Philadelphia, San Francisco, Washington
Systems of teams that had a positive turnover differential the previous season
— Only three of the 14 teams since 2009 that had a turnover differential of + 1.0 or better per game improved their records the next season. The average won-lost percentage decline was 10.6% (8% ATS), or almost two wins. New England qualified on this angle last year and dropped from 12-4 to 7-9.
Teams affected in 2021: None. Tennessee had the top regular-season turnover differential at + 0.7.
— Teams that had a positive turnover differential and won 10 or more games against the spread are fade teams in the next season. Of 70 such teams since 2009, 48 had won-lost-records that declined, by an average of 10.5% outright and 11% against the spread. Of the 65 that reached the playoffs, 26 failed to do so the next season.
Teams affected in 2021: Baltimore, Buffalo, Green Bay, Miami, Pittsburgh.
— Since 2009, there have been 36 teams with a turnover differential of + 5 or better in a season that failed to reach the playoffs. Only 11 reached the postseason the next year, and only 14 improved their records. These are typically play-against teams, as failing to reach the playoffs does not provide momentum the next season.
Team affected in 2021: Miami.
— Only seven of the last 30 teams that had a positive turnover differential and won seven or fewer games against the spread in a season reached the playoffs the next season, and only 13 improved, although Indianapolis, Pittsburgh and Washington last year were among those minority teams.
Teams affected in 2021: Atlanta, Cleveland, Kansas City, New England, Seattle, Tennessee.
— Of the 12 teams whose ATS won-lost percentage declined by 31% or more from one season to the next since ’09, all had a positive turnover differential of + 4 or better the previous season.
Teams potentially affected in 2021: Baltimore, Buffalo, Cleveland, Green Bay, Indianapolis, Kansas City, Miami, New Orleans, Pittsburgh, Seattle, Tampa Bay, 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 2001, the NFL has had 48 teams that won 10+ games despite scoring fewer than 23 points per game. In the next season, only eight of these teams improved, while 37 dropped, by an average of 4.3 games in the win column.
Teams affected in 2021: None. The Los Angeles Rams were closest at 10-6 and 23.3 ppg.
— Fairly steady season-to-season improvement has been made by the group of teams that have won six or fewer games despite scoring 22+ ppg. Since 2000, only three of those 25 teams were worse the next season, and the average win improvement was 2.5.
Teams affected in 2021: Atlanta, Dallas, Detroit, Houston, San Francisco.
— Since 2000, some 60 teams somehow won six or fewer games despite allowing 23 or fewer points per game. In the next season, 43 of those teams, or 71.7%, improved in the win column, and the average improvement of that group was 3.76 wins.
Team affected in 2021: New York Giants.
— Teams that have won 10 or more games despite allowing 23+ ppg showed consistent season-to-season decline. Over the last 22 seasons, only two of the 24 teams were better the next season, and the average drop was 3.04 wins.
Teams affected in 2021: Buffalo, Cleveland, Green Bay, Seattle, Tennessee.
— In the last 20 seasons, 11 teams have averaged 27+ ppg but did not make the playoffs. Their combined record the next season was 109-67, good for 61.9% and an average of 9.9 wins. Only three of those teams did not make the playoffs, and two, the 2009 Saints and 2020 Buccaneers, won the Super Bowl.
Team affected for 2021: Las Vegas.
— If you examine positive point differential with losing records, the last 14 teams that had this combination improved their won-lost record the next season, including the 2017 Super Bowl champion Eagles and the 2020 champion Buccaneers. The average win total for these teams was 10.0, with eight winning at least 11 games, and the average win improvement was 3.3.
Team affected for 2021: Washington.
— When considering negative point differential with an 8-8 record or better, only five of the last 25 teams to achieve this dubious status went on to a better season the next year. The average drop was a minimal 1.4 wins per season, but the margin of making the playoffs for teams like this was already small.
Teams affected in 2021: Las Vegas, Cleveland.
Combination systems using the statistical characteristics detailed already
— Six teams have gone 7-9 or worse in a season despite a positive turnover differential and scoring differential, and five have made the playoffs the next season, improving by an average of 4.2 wins.
Teams affected in 2021: No teams qualify. Washington was closest with a 7-9 record, -0.25 turnover differential and + 0.4 scoring differential.
— Eight of the last 12 teams that had negative turnover differential but positive score differential and didn’t make the playoffs did so the next season, including the Bucs in 2020.
Teams affected in 2021: None. Chicago and Washington meet the statistical criteria but also made the playoffs. In the Bears’ case, it was because of the expanded wild-card field.
— Only seven of the last 35 teams that had a positive turnover differential but negative score differential qualified for the playoffs in the next season.
Teams affected in 2021: Atlanta, Carolina, Cleveland, Los Angeles Chargers, New England.
— All but two of the 21 teams since 2009 that had a negative turnover differential and were outscored by more than 10 ppg improved their won-lost records the next season, by an average of 25%, or 4.0 wins. Four of those teams made the playoffs, and 12 improved by four or more wins.
Team affected in 2021: Jacksonville.
— Only seven of the 33 teams since 2009 that had a positive turnover differential and outscored opponents by more than 8.0 ppg improved their won-lost records the next season. The average won-lost percentage decline was 16% (13% ATS), or about 2.6 wins.
Teams affected in 2021: Baltimore, Green Bay, New Orleans, Tampa Bay.