When Jim Brown took time out from filming in London for “The Dirty Dozen” to announce his retirement from the NFL, news reports called him the greatest running back in league history.

Ten others have supplanted Brown atop the all-time rushing list since that day in 1966, but Brown remains the standard for the position because of his elite production. He led the league in rushing eight times in nine seasons. He topped 1,500 yards with 21 total touchdowns in his final season — totals that would have ranked second and first, respectively, in the NFL last year despite teams now playing three additional games per season.

What should Hall of Fame statistical production look like for a running back? I solved for that question regarding wide receivers recently and will do the same for running backs here, using data from Pro Football Reference.

There might never be another Jim Brown, but the Week 4 game Sunday between the Tennessee Titans and Indianapolis Colts delivers two of the best backs today. Tennessee’s Derrick Henry led the league in rushing in 2019 and 2020. Jonathan Taylor, in his third season and still only 23, rushed for more yards in his first two seasons (2,980) than all but six others in NFL history.

It’s this elite production we are seeking to measure more than yardage compiled well past players’ primes.

In evaluating wide receivers, I averaged percentiles for where each player ranked in receiving yardage during his eight best seasons, after requiring at least 7,000 career yards for inclusion. Jerry Rice and Don Hutson came out on top, with Randy Moss next and a few surprises mixed in. By comparing players against their peers in each season, we adjust for eras.

With running backs, who generally have shorter windows of elite production, I settled on six seasons instead of eight. Quite a few top backs did not even have a seventh season to evaluate, but all of them had at least six, affirming that the six-year cutoff was optimum. To qualify, players had to rank among the top 100 running backs in all-time rushing yardage.

To account for receiving production among these top rushers, I averaged percentiles for where each ranked in scrimmage yardage, not just rushing yardage, during their six best seasons from scrimmage. Versatile backs such as Marshall Faulk, Tiki Barber, Ricky Watters, Matt Forte and Roger Craig climbed as a result. Others, like Joe Perry and Jim Taylor, would have ranked higher if only rushing yards were considered.