The A.F.C. North and South look like prime candidates for a shake-up.
How often does a team finish first one season, then sink to last the next? And how often does the opposite happen, with a last-place team improving to top the table?
In the N.F.L., it happens all the time.
In each of the last four seasons, and in eight of the last nine, at least one team that topped its division (or tied for first) the previous season slipped to last place the next.