The theme of the 2010s and 2020s in college football has been power concentration. Things have grown pretty predictable, with Alabama winning six national titles in 12 years under Nick Saban; Ohio State, Clemson and Oklahoma ripping off long runs of conference domination; and now Georgia winning back-to-back national titles.
It's early in the College Football Playoff's lifespan, but it's possible that we're witnessing a concentration of power at or near the top of the sport, something that expansion to a 12-team CFP might or might not address. Or it's possible we're just witnessing another, similar act in college football's history -- it is, after all, a sport that has forever been lorded over by a ruling class of dominant schools.
Is the ruling class more dominant than usual? What shifts have we seen over time? For questions like these, SP+ can come in handy.
While the version of SP+ presented weekly during a given season is based on a large number of predictive factors, I have come up with a version based solely on points scored and allowed that, at the lower levels of the sport, can serve to make solid projections. I applied those same methods to the games going back to 1883, when football's scoring rules became mostly what they are now. (You can find all ratings here.)
Starting with the 1920s, I looked at which teams most thoroughly dominated the sport from decade to decade, using SP+ percentile averages for each team and each decade. How much do these lists change over the decades? What can these averages tell us about how things have evolved over the past 100 years and how much things are evolving now?
Let's dive in.