Recently I looked at team defense through the lens of Win Probability Added (WPA). Every play changes a team's chances of winning, and we can sum all the ups and downs into a total WPA for any player, team, offense, or defense. In this post, I'll look at team offense.
As with defenses, one offense might be the best in yards and another might be the best in yards per play. Yet another offense might be the best in terms of points. WPA can cut through all that, and tell us which squads made the biggest impacts on winning.
WPA captures the things that other stats cannot. For example, consider an offense leading by one point with 3 minutes left in the game. A series of modestly successful runs to convert a first down and kill the clock won't make fantasy fans happy, but it effectively clinches the win. A stop and a punt would typically give the opponent over a 30% chance of winning, so that grinding first down conversion may mean more in terms of winning than almost any other series all season.
The WPA listed for each year are raw totals including playoff games. They effectively say 'this is the number of games a team would win given a completely average offense and special teams.' For example, the 2000 Colts offense posted a +4.5 WPA. This suggests the Colts offense would have won 12.5 games had their defense and special teams simply held serve, making absolutely no contribution toward winning.
I've also added a column for WPA per game to account for teams with playoff appearances. You could think of this number as how much a defense added to their team's chance of winning any given game. For example, the Indianapolis offense (+0.23 per game) would turn a 50% chance of winning a game into a 73% chance.
Click on the table headers to sort:
I was surprised to see that the Colts' 2006 season (7.7 WPA) eclipses the Patriots' undefeated 2007 season (+6.5). New England broke many offensive records that year, but running up the score doesn't add much to WPA. A late touchdown on top of a 0.98 WP doesn't make much of a difference.
The most inept team of the decade belongs to Chicago so far, but Detroit might overtake them this year. The worst single-year offense belongs to the 2004 Dolphins.