The preseason S&P+ projections are a simple mix of three factors: recent history, returning production, and recruiting. To come up with 130-team projections, I create projected ratings based on each factor. Here’s how the process works:
Recruiting is easy. I create a rating based on these two-year recruiting rankings. The recruiting-based projection makes up about a quarter of the overall S&P+ projection.
For returning production, I apply projected changes (based on each team’s returning offensive and defensive production, which are on different scales) to last year’s S&P+ averages. The projection based on returning production accounts for a little more than 50 percent.
For recent history, I get a little weird. I found last year that the previous year’s S&P+ ratings — which make up the starting point for the returning production figures — were carrying a little too much weight. So what you see below is a projection based solely off of seasons two to five years ago. Recent history now carries less weight in the overall formulas, under 20 percent.