In 2016, 146 of 256 regular season games finished with a margin of victory of 8 or fewer points. That’s an incredible 57.0% of all games being decided by one score, which makes the 2016 season one of the most competitive in NFL history. If not the most competitive. In 2015, 54.7% of all games were decided by 8 or fewer points; prior to that, no other season since 1960 finished with 54.1% or more games being decided by one score.
The graph below shows the percentage of all games since 1960, by year, where the final margin was 8 or fewer points:
If we use 7 points as our cut-off instead of 8, the 2016 season was also a record-breaking one. Last year, for the first time since at least 1960, 53% of all games were decided by a touchdown or less:
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And here’s one graph with both 7- and 8-point margins depicted:
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There are many takeaways from this — it probably is a sign of greater parity, at least in the sense of competition within a season. It also, to some extent, devalues the myth of fourth quarter comebacks. With so many close games, most games are going to have a fourth quarter comeback, or at least a chance for one. And it also means records may be less sticky from year-to-year: we know that records in close games don’t hold much predictive value. Well, the larger percentage of a team’s games that are close, the less predictive value that team’s overall record will have.