Division Power and FWDP
APR already gives a way to compute a power index for individual teams. Division power can be computed by averaging teams power index on a per-division basis.
Just as team power indexes can be computed for each week of the regular season, division power indexes can be computed for each week as well. For the purposes of analyzing the division power of Super Bowl winners, I will use the division powers from the final week of the regular season.
For the purpose of future discussion, I will abbreviate Final Week Division Power as FWDP.
Super Bowl Contestants by Division Power
The the list of the strongest divisions by FWDP since 1960 has the divisions of lot of Championship and Super Bowl winning teams on it. Which naturally suggests there might be a correlation between strong FWDP and winning the Super Bowl.
Looking at the seasons from 1990 to 2007, there appears to be a very strong correlation between strong FWDP and winning the Super Bowl:
| Year | High FWDP | Result | Low FWDP |
| 1990 | New York Giants | beat | Buffalo Bills |
| 1991 | Washington Redskins | beat | Buffalo Bills |
| 1992 | Dallas Cowboys | beat | Buffalo Bills |
| 1993 | Dallas Cowboys | beat | Buffalo Bills |
| 1994 | San Francisco 49ers | beat | San Diego Chargers |
| 1995 | Dallas Cowboys | beat | Pittsburgh Steelers |
| 1996 | Green Bay Packers | beat | New England Patriots |
| 1997 | Green Bay Packers | lost to | Denver Broncos |
| 1998 | Atlanta Falcons | lost to | Denver Broncos |
| 1999 | Tennessee Titans | lost to | St. Louis Rams |
| 2000 | Baltimore Ravens | beat | New York Giants |
| 2001 | New England Patriots | beat | St. Louis Rams |
| 2002 | Oakland Raiders | lost to | Tampa Bay Buccaneers |
| 2003 | New England Patriots | beat | Carolina Panthers |
| 2004 | New England Patriots | beat | Philadelphia Eagles |
| 2005 | Pittsburgh Steelers | beat | Seattle Seahawks |
| 2006 | Indianapolis Colts | beat | Chicago Bears |
| 2007 | New York Giants | beat | New England Patriots |
That's a 14-4 record (77.7%) for that span of games, which suggests that FWDP is a strong indicator of which team wins the Super Bowl.
Something Happened in 1990
I chose the cut-off year of 1990 advisedly. The results from 1970 to 1989 are quite different:
| Year | High FWDP | Result | Low FWDP |
| 1970 | Dallas Cowboys | lost to | Baltimore Colts |
| 1971 | Dallas Cowboys | beat | Miami Dolphins |
| 1972 | Washington Redskins | lost to | Miami Dolphins |
| 1973 | Miami Dolphins | beat | Minnestoa Vikings |
| 1974 | Pittsburgh Steelers | beat | Minnesota Vikings |
| 1975 | Pittsburgh Steelers | beat | Dallas Cowboys |
| 1976 | Minnesota Vikings | lost to | Oakland Raiders |
| 1977 | Denver Broncos | lost to | Dallas Cowboys |
| 1978 | Pittsburgh Steelers | beat | Dallas Cowboys |
| 1979 | Pittsburgh Steelers | beat | Los Angeles Rams |
| 1980 | Oakland Raiders | beat | Philadelphia Eagles |
| 1981 | Cincinnati Bengals | lost to | San Francisco 49ers |
| 1982 | Washington Redskins | beat | Miami Dolphins |
| 1983 | Washington Redskins | lost to | Los Angeles Raiders |
| 1984 | San Francisco 49ers | beat | Miami Dolphins |
| 1985 | New England Patriots | lost to | Chicago Bears |
| 1986 | Denver Broncos | lost to | New York Giants |
| 1987 | Washington Redskins | beat | Denver Broncos |
| 1988 | Cincinnati Bengals | lost to | San Francisco 49ers |
| 1989 | San Fracisco 49ers | beat | Denver Broncos |
That's a 11-9 record (55.0%) for that span of games, which suggests that there is little or no correlation between FWDP and which teams won the Super Bowl during that era.
What Happened in 1990?
If you've followed the NFL for any length of time, you know that they are constantly changing the rules. Often to protect the safety of the players, or to make the game more exciting.
A number of significant changes were made during this era. Free agency and the salary cap were introduced. The post-season was expanded from 5 playoff teams per conference to 6.
I would like to have a definitive answer to put here. However, given the small sample space, the number of rule changes, and the fact that there's no way to "replay" old seasons with different rules, it's probably impossible to say what caused the change.
I would also like to be able to make some claim that the 1990-2007 correlation will continue in the future. But with no specific cause to point to, there's no way to make the case that some subsequent change won't undo (or hasn't already undone) the effect.
The Future
Following the final week of the 2008 season (and for each future season I keep FSPI going), I will post the FWDP for all 8 divisions. In the pick result post following the Super Bowl, I will link back to the FWDP post, note whether or not the team with the better FWDP index won, and update the 1990-present tally.
