We start from the year 1970 as it marks when the AFL officially disintegrated.
One thing to note: we compiled our league rankings for each team using the order listed in the standings on NFL.com. Due to this, there may be some discrepancies in the ranking of teams who finished with the same record in a given year if we consider tiebreaking procedures. But the point of the graph is to give more of a general idea—a sweeping idea of how a team progressed and regressed over the course of several decades.
In regards to the actual data, here are just a few points that stuck out to me:
1. The Patriots’ excellence in the 2000s
2. The Bucs’ stagnancy in the cellar of the league around the 1980s.
3. The 49ers and Dolphins’ dominance in the 1980s.
4. The Cardinals have never been one of the top teams in the league (of course, they did make the Super Bowl in 2009 due to making playoff upsets).
5. The ineptitude of the Raiders since the early 2000s.