unofficial pre-1982 sack numbers have been updated

from https://www.sports-reference.com/blog/2021/07/pre-1982-sacks-added-to-pro-football-reference/

Pre-1982 Sacks Added To Pro Football Reference
Posted by Mike Lynch on July 12, 2021

The NFL has only officially counted player sacks since 1982, which means sack records and leaderboards present an incomplete history of pass rushing. In many cases we accept these holes in the official record and move on. After all, we don’t know how many rushing yards Jim Thorpe had, passing yards Paddy Driscoll had or even how many blocked shots Wilt Chamberlain had. Heck, we don’t even “officially” know how many tackles anyone had in 2020 (or any other season). However, thanks to Official Gamebooks, ‘unofficial’ tackle totals get published in many places (including here). In the case of sacks, thanks to decades of research by John Turney and Nick Webster, we have a very thorough accounting of the statistic all the way back to 1960. Given that accounting for these ‘unofficial’ statistics allows us to paint a richer picture of the history of the game, we think it is a no-brainer to present them on Pro Football Reference, allowing fans to gain a deeper appreciation of some of football’s biggest stars in the 1960s and 1970s. This isn’t terribly different from presenting RBI totals for baseball players from before 1920 (the first season the statistic was “official”). These additions allow us to print year-by-year and career sacks totals for not just legends such as Deacon Jones (173.5), Jack Youngblood (151.5), Alan Page (148.5), Carl Eller (133.5) and Joe Greene (77.5), but also for less recognized stars like Coy Bacon (130.5), Cedrick Hardman (122.5) and Jack Gregory (106.0) whose greatness and impact can now be more readily quantified.

Turney and Webster, stalwart members of the Pro Football Researchers Association, have been compiling these numbers for nearly 30 years. To read a bit about their work and methods, we would recommend checking out these articles from the Hartford Courant, New York Times and ESPN’s old Page 2. The important things to know are that these numbers are based upon review of official play-by-plays, watching game film, photographs and coaches’ stats. The work continues to this day as new information is discovered, particularly for numbers from the early 1960s.

It’s remarkable how thorough the research is, given the many obstacles. 99% of sacks from the 1970 merger to 1981 are accounted for. From 1966 to 1969, it’s closer to 95% (both AFL and NFL). 1961-64 is about 80% coverage. About two-thirds of sacks in 1960 are accounted for.

With the new data incorporated into the site, here’s how the “unofficial” NFL sacks leaderboard (back to 1960) looks:

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