I was interested in identifying the national average expectations for a punting team in terms of field-position value and then measuring each punt for each team against that value. I first collected the data from every non-garbage time punt in the last three years, 19,862 punts in all. From each drive-ending punt position, I then calculated the average starting field position for the opponent's next drive. For instance, the 403 punts from midfield in the last three years netted an average starting field position for the opponent at its own 18-yard line. The 413 punts from a team's own 20-yard line in the last three years netted an average starting field position for the opponent at its own 41-yard line.
Every yard line translates into an expected field-position value. An average offense against an average defense is expected to score 1.2 points per possession from its own 18-yard line and 2.2 points per possession from its own 41-yard line. In the same manner that offensive efficiency is calculated, Punting Efficiency (PE) is simply the actual value of post-punt field position divided by the expected value of post-punt field position, minus one (in order to represent a team's efficiency above or below average). A good punt team will have a PE below zero, pinning opponents with less starting field position value than expected. A good punt return team will have a PE above zero, creating more starting field position value than expected.
It is important to note that this metric should be attributed to the respective punt unit and punt return unit, not just the punter or punt returner involved. It does not take into account the hang time or roll of the punt, the coverage, etc. Rather, the resulting field position of the entire play is taken into account. Punts returned for a touchdown are credited with a field position value of 6.96 points. Punts that are fumbled are credited with the field position value of the recovered fumble. PE does not include any adjustment for the strength of opposition faced.
