The stat Mornhinweg pays attention to

Marty Mornihinweg uses the 'Yards Per Attempt' stat to measure his quarterback's play. (Yong Kim/Staff Photographer)

During the season, I use several numbers here to try and get a feel for what's really going on with the Eagles.

Sites like Football Outsiders and Pro Football Focus continue to gain traction as football fans and reporters attempt to figure out which numbers are useful and make sense, and which numbers are essentially worthless.

To that end, Seth Wickersham of wrote an interesting piece about a stat that Marty Mornhinweg uses to evaluate quarterbacks: Yards Per Attempt (YPA).

"That statistic not only correlates highly with winning and scoring, but it shows that you get big chunks of yardage in the passing game," Mornhinweg said.

Wickersham did a little bit of research, using the Elias Sports Bureau, and found that 72 percent of the top-five passers in YPA in the past 10 years have led their teams to the playoffs.

Now, that might be a little bit of a leap. Yards per attempt depends on a number of different things. Yes, one of those things is the play-calling and how often the coordinator/coach is willing to take shots down the field.

But there's also personnel. How fast are the receivers? Can the offensive line protect for those shots downfield? Back in May, I took a look at Michael Vick, Donovan McNabb and the Eagles' YPA over the years. Here's the chart:

Eagles' QB YPA
Vick in 2010 8.1
McNabb in '09 8.0
McNabb in '08 6.9
McNabb in '07 7.0
McNabb in '06 8.4
McNabb in '05 7.0
McNabb in '04 8.3
McNabb in '03 6.7
McNabb in '02 6.3
McNabb in '01 6.6
McNabb in '00 5.9

As you can see, McNabb and Vick had almost an identical YPA the past two seasons. Both played under Mornhinweg. Both had weapons like DeSean Jackson and Jeremy Maclin at their disposal.

In 2006, a variety of players contributed: Brian Westbrook, Reggie Brown, Donte' Stallworth, L.J. Smith and Hank Baskett, who averaged 21.1 yards per reception.

In 2004, not only did the Eagles have Terrell Owens, but Todd Pinkston averaged 18.8 yards per reception.

Here are the league leaders in YPA last season:

 Philip Rivers
 Aaron Rodgers
 Ben Roethlisberger
 Michael Vick
Tom Brady
 Jay Cutler
 Matt Schaub
 David Garrard
 Joe Flacco
 Jon Kitna
Eli Manning 7.4

If you take a closer look, you can see how Vick's number related to his overall play. In that Tuesday night game against the Vikings, he averaged a season-low 6.1 yards per attempt, which translated to a season-low 74.1 QB rating and certainly contributed to the 24-14 loss.

But in the playoff loss to the Packers, Vick averaged 8.1 yards per attempt. If you remember, the Eagles were actually able to hit on a few plays downfield in that game. He only completed 55.6 percent of his passes though, Vick's second-worst mark of the season.

In other words, I like YPA. It's a simple stat. You can find it easily online, and it is a good gauge of efficiency and downfield passing.  Overall, though, there is so much more that goes into evaluating a quarterback's success in the passing game.

And with Vick, specifically, it gets even trickier when judging his overall performance because of the plays he makes with his legs.

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