A new quarterback rating developed by ESPN's Stats and Information group will be unveiled on Friday.
The Total Quarterback Rating takes into account a larger number of variables than the nearly 40-year-old NFL Passer Rating system -- including down and distance, field position and importance of the game situation.
The new QBR weighs rushes, passes, sacks, fumbles, interceptions and penalties and calculate the per-play net impact of the quarterback. As an example, a pass completion on third down that yields a first down is worth more than a completion for the same yardage that doesn't result in a first down. Plays in closely contested games also count for more in the system.
It will be based on a 100-point scale, with ratings in the 70s being Pro Bowl caliber, and a rating of 50 will be considered average.
"The Total Quarterback Rating is designed to be a single comprehensive stat that demonstrates effective quarterback play, and we're excited to introduce it to fans on ESPN this season," said ESPN senior director of production analytics Jeff Bennett, who developed the ratings along with co-workers Dean Oliver, Alok Pattani and Albert Larcada. Menlo College professor Ben Alamar also participated.
The QBR will be unveiled in an ESPN Year of the Quarterback special on Friday, Aug. 5 at 8 p.m. ET. As part of the program, the top five NFL quarterbacks from the past three seasons will be unveiled. There will also be a comparison of QBR against the NFL Passer Rating system.
"The position is played so differently now than when the NFL Passer Rating was adopted in 1973," Bennett said. "We created QBR to account for all the important categories as well as the game situations in which plays are made to help tell the entire story about a quarterback's performance."
Oliver joined ESPN as a director of production analystics earlier this year after a career in pioneering NBA analytics, including a job with the Denver Nuggets. Alamar does statistical analysis for the Oklahoma City Thunder and has consulted with the San Francisco 49ers.
ESPN analysts Trent Dilfer, Jon Gruden and Ron Jaworski were also involved in setting up the new rating system.