Inside the Numbers: Run Impact Percentage, and Turnovers

By: Chris Coleman | Lead Analyst and Columnist
Dax Hollfield, Virginia Tech
Dax Hollfield is having a rough season. (Ivan Morozov)

Today we’ll introduce you to another part of the Pro Football Focus library by talking about run impact percentage.  This is a metric that determines how well a defensive player performs against the running game, and it’s broken down into two parts…

  • Positive Run Impact %: The percentage of running plays in which the defender earned a positive grade.
  • Negative Run Impact %: The percentage of running plays in which the defender earned a negative grade.

(Note: Everything that isn’t a positive or a negative is graded as neutral.  Neutral grades are fine, as long as that player isn’t surrounded by a bunch of guys with negative grades.)

As a basis for comparison, the ACC average is 11.3 positive run impact percentage, and 9.4 negative run impact percentage.

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