To answer that question we must consider five aspects of the quarterback position: passing, rushing, quality of supporting personnel, quality of opposition, and luck.
Typically though we evaluate a quarterback's effectiveness by only considering his passing game, using the standard Passer Rating formula:
As you can see, this formula considers pass completions, yards gained, touchdown passes, and interceptions versus pass attempts. It ignores rushing, which is then best expressed as rushing yards per game.
Situational context such as when the pass attempt is on a third down or how much time is remaining is not taken into consideration, nor is what is at stake, the quality of the opposing defense or the ability of the offensive line to protect the QB.
Thus Peyton Manning's
touchdown pass when the Broncos
were down 36-0 in the third quarter of the 2014 Super Bowl
counts for just as much as Eli Manning's
13 yard touchdown pass with 35 seconds to play and the Giants
down by 4 in the 2008 Super Bowl
. Likewise the devastating toll of Brett Favre
throwing for an interception with 19 seconds to play in the 2009 NFC Championship game
is counted the same as an intercepted pass in the first quarter of a week 2 game. Also, the QB is charged with an incomplete pass when the wide receiver drops a perfect pass, and he is charged with an interception when the receiver tips the ball and it's then recovered in the air by a corner back.
So using only the passing statistics, who is the greatest quarterback of all time, with at least 750 pass attempts? It's not Peyton Manning
, it's not Tom Brady
, and it's not Joe Montana
. It's Aaron Rodgers
and Russell Wislon
Here is a clip of the full ranking,
which we can also tweak to give only a certain range of years and minimum number of pass attempts: (mouse over column headers for explanation) Full ranking... Aaron Rodgers
and Russell Wislon
are so high up because they make so few mistakes, very few interceptions. Intuitively, we'd expect Eli Manning
, Brett Favre
, and Dan Marino
to be in the top 10 of this list while we wouldn't expect Steve Young
or Philip Rivers
to be so high up. Eli Manning
has been Super Bowl MVP twice, yet his numbers leave him at #49 in the ranking. Brett Favre
and Dan Marino
(#21 and #25, respectively) were very reliable quarterbacks and extremely popular but they made a lot of mistakes.
The younger crop of quarterbacks such as Russell Wislon
, Colin Kaepernick
, and Robert Griffin III
seem to come with enhanced running ability whereas the current greats seem to be monolithic passers. Peyton Manning
rushes for only 3.45 yards per game!
Stay tuned for an enhanced formula that considers rushing and game context.