Adjusting for eras, Brees far from Unitas
October, 4, 2012
By Alok Pattani, ESPN Stats & Info | ESPN.com
AP Photo/NFL PhotosJohnny Unitas and Drew Brees are tied for the NFL record with touchdown passes in 47 straight games.Drew Brees is currently tied with Johnny Unitas for the longest streak of games with at least one touchdown pass in NFL history.
With Brees set to eclipse Unitas’ mark of 47 on Sunday night in New Orleans, we thought it would be interesting to compare the two streaks by taking into account the different eras in which they occurred.
Unitas’ streak encompassed five seasons from December 1956 to December 1960 and came at a time when passing was much less common than it is today.
In 1956, for example, pass plays were less than 40 percent of a team’s overall plays, and the average team threw for less than 150 yards per game. Unitas threw only nine touchdown passes that season but was tied for seventh in the NFL, with only Green Bay’s Tobin Rote (18) recording more than 12 passing scores.
While league-wide passing increased significantly in the short span of Unitas’ run – pass plays were up to nearly 50 percent frequency in 1960, when Unitas led the league with 25 touchdowns through the air – it was nowhere near what we see today.
Nowadays, teams look to throw nearly 60 percent of the time, they average well over 200 passing yards per game, and about 10 quarterbacks a year throw for 25 scores.
To compare the two 47-game streaks more directly, we can look at how likely it is for a team to have at least one passing touchdown in a given game today, and how likely it was back during the late 1950s. This is not specific to Unitas and Brees, but rather the eras that they each played in.
NFL teams recorded at least one passing touchdown in 73 percent of all regular season games from 1956 to 1960, compared to 79 percent from 2009 to 2012 (the span of Brees’ streak). Essentially, it’s easier to pass for a touchdown in a game now than it was back then.
Given the lower rate of passing touchdowns, we can calculate that a 47-game touchdown pass streak was 43 times more unlikely in the late 1950s than in today’s NFL.
This basic calculation ignores aspects of longer seasons or careers, that there are more quarterbacks around to chase the record, and that there may be a different level of variation in skill among the best quarterbacks. Nevertheless, this simple era adjustment shows just how statistically different these two streaks are despite their identical length.
In fact, given the likelihood of passing touchdowns in the last four years compared to the Unitas days, a 63-game streak today is about as likely as a 47-gamer back in the late 1950s. By that measure, Brees still has a season’s worth of work to do.
So while Drew Brees should be applauded when he breaks Johnny Unitas’ mark this Sunday, keep in mind that statistically speaking, Unitas’ streak is still much more impressive given the era in which it came.