Football folks love to rank their NFL teams by all kinds of stats and quote them incessantly. Now, rankings can give a general idea of how you compare to other teams but not give you an idea of how meaningful that comparison is. For example, is being ranked 5th a lot better than being ranked 9th or 15th? Is being ranked 1st really that much better than a team ranked 3rd or 5th?

Football, like many sports, is a zero sum game - for every winner there is a loser. Therefore it's important to know how much better you are than another team in different areas. Why? Because the only stat that really matters - how many games you win - is dependent on how you perform compared to your opponents, in many different areas.

In this article, instead of just ranking teams, a bell curve system is used below to group teams with similar stats into the same groups and assign a performance grade to that group. That's right, a bell curve, just like they used in school. For every stat the average for all teams is calculated along with the standard deviation. [Standard deviation is just a fancy way to measure the differences of teams from the average.] Then the teams are grouped into categories.

The top 1 or 2 teams may be desginated as "Elite", the next best 2-4 or 5 teams designated "Very Good", etc., all the way down to "Terrible." The groupings are color coded to make them easier to identify while still showing the stat. If your team has a lot of "black and blue" stats then your team is probably black and blue from the poundings it is taking from other teams. [Black and blue are not good colors. Coaches get fired over black and blue rankings.] Sometimes teams are all bunched up together around the average so there are no Elite or Terrible teams for that stat. That just means nobody stood out enough from the rest of the pack to be labeled that way.

The best teams are color-coded red while the ones in the middle are a wishy-washy yellow-green, just like their stats. See the color key below for tongue-in-cheek descriptions.

Sometimes 20 teams will be designated as below average instead of the expected 10 to 11 teams. [In general, about 2/3rds of the teams will be above and below average]. That just means their stats are very close to each other.

And some of the groupings are downright silly. Do you really care if your team is bad or very good in the number of fair catches it had last year? Probably not. But if you do then you're in heaven because that stat is graded too. You also probably need to get a life.

For the real statisticians out there that are frothing at the mouth right now over the imprecise wording and the questionable methodology used here, I say this: Go away, have a beer or something and don't come back until you realize it is only a game. Although adding groups provides more info than just a straight ranking, it could be improved. The population variance was used for the groupings as the population was defined as 1 years worth of stats and the entire year was used. "Average/game" stats are totals for the year divided by 16, not 16 game averages averaged together. So there is a large sample size, roughly 1,000 plays per team per year. The groupings are: +2 stdev (standard deviations) = Elite, 1 to 2 stdev = Very Good, mean to +1 stdev = Above Average, -1 stdev to mean = Below Average, -1 to -2 stdev = Bad, and below -2 stdev = Terrible. Better now?

And finally, if someone tells you that your team sucks, you can now respond with something half-witty like "No, actually the statistics prove we're just kinda crummy." Unless your team is the Lions or the Bengals in which case the best response is to look down at your feet and mumble agreement.

Bell Curve Color Key

If you think the wording is a little harsh then imagine you are a manager in a small company that sells accounting software to bigger companies and there are 31 other competitors that also sell accounting software. If your department, the one YOU manage is ranked 18th in customer satisfaction, cost or quality then your boss may let it slide but you are not getting any year-end performance bonuses. If your department is ranked 29th your boss may want an action plan to immediately correct your poor performance and the president of the company is probably monitoring your progress. I'm guessing "kinda crummy" is the nicest wording they are using to describe you. And if you're ranked 31st or 32nd then you may not know what words they're using to describe you because your successor is cleaning up your mess.

Don't forget that while it's a game to us, it's a business to the coaches and players and how they earn a paycheck. Their business metrics - how their job performance is measured - are the kind of stats listed below. They take them seriously.

2008 Regular Season Stats

The tables below look at 4 main categroies: overall game, passing, rushing and return stats. Within each category, 3 "sub-categories" are listed: Offense, Defense, and Diff. Offense is how that teams offense performed. Defense is how other teams did against their defense, and Diff is just the difference between the two: Offense stat - Defense stat. The numbers came from NFL, ESPN and FoxSports web sites.

I was hoping the "Diff" table would help point to teams with winning records. After all, it doesn't matter if your offense is average as long as your opponents offense is worse when playing you. Just ask Pittsburgh. Their average offense and Elite defense won them the Superbowl, again. The DIFF in overall yards/play is the best indicator followed by Rushing yards/game for the 2008 season, but more data is needed. The jury may be out on the usefulness of the Diff table, but it is interesting.

     Click on the table headers to sort.     ** Indicates a playoff team.

OFFENSE Game Stats

DEFENSE Game Stats

Off-Def DIFF Game Stats

OFFENSE PASSING Stats

DEFENSE PASSING Stats

DIFF Passing Stats

OFFENSE RUSHING Stats

DEFENSE RUSHING Stats

DIFF Rushing Stats

OFFENSE/Own Returns Stats

DEFENSE/Opp Returns Stats

DIFF Return Stats