No team has won back-to-back Super Bowls since the 2003–2004 Patriots, which means the last eight champions have failed in their bid to repeat. Three of them — the ’06 and ’09 Steelers and the 2012 Giants — failed to even make the playoffs. Some writers have used this as a reason to suggest that Baltimore may be subject to a Super Bowl curse.

Of course, the idea of a curse — or a sample of data — doesn’t mean much in the abstract. Let’s look at some numbers on the 42 Super Bowl winners between 1970 and 2011. On average, those teams had a 0.676 winning percentage in Year N+1 (i.e., the year after they won the Super Bowl). Thirty of those teams made it back to the playoffs, one out of every six of those teams won the Super Bowl, and three more lost in the Super Bowl (the ’78 Cowboys, ’83 Redskins, and ’97 Packers). Some would use this as evidence of a curse — i.e., only 9 of 42 teams made it back to the Super Bowl — but again, we need some context.

I decided to compare Super Bowl winners since 1970 to three other teams: Super Bowl losers, the Simple Rating System champion from that season (which may or may not be a team that made it to the Super Bowl), and an average of all playoff teams from that year. On average, Super Bowl winners have the best winning percentage of that group in the following year. And Super Bowl winners are the most likely to win the Super Bowl. Super Bowl winners are less likely to lose in the Super Bowl the next season than the Super Bowl loser (thanks, Buffalo) or the SRS champ, but the defending champion is still the team most likely to make it back to the Super Bowl. The two Super Bowl teams and the SRS champ also make the playoffs the following season just north of 70%, well ahead of the average playoff team.

The chart below shows all of these results, which makes it pretty clear that being the defending Super Bowl champion is a good thing for future prospects (and it’s not too shabby on a resume, either):
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