5.5 in the regular season and .5 in the postseason.
Through the 2013 season, LaMarr Woodley has 57career sacks during the regular season. He also has 11 postseason sacks.
There isn't really a record kept for fewest sacks in a season by a player, as there are thousands of NFL players who have not had any sacks. Michael Strahan holds the record for most sacks in a season, at 22 1/2.
In the 2007 NFL season, there were 1102 total sacks so the average team was sacked 2.2 times per game (34.4 times per season). In 2006, there were 1164 sacks averaging out to 2.3 sacks per game per team (36.4 sacks per season) and in 2005, there were 1182 sacks averaging out to 2.3 sacks per team per game (36.9 sacks per season).
That was 2004. He led the NFL in sacks that season.
The linebacker with the most sacks in an NFL season is Justin Houston of the Kansas City Chiefs. He finished with 22.0 sacks in 2014.
Reggie White set the Eagles single season record with 21 sacks in 1987.
In 1981 Klecko had 20.5 sacks and Gastineau had
Mike Berg of the Green Bay Packers had 9 sacks in the 1979-1980 season.
Unfortunately, Karras retired after the 1970 season. The NFL did not begin recording sacks officially until 1982.
Through 12 games of the 2012 season that is DE Aldon Smith of the 49ers with 17.5 sacks.
Elvis Dumervil of the Denver Broncos. He had 17 sacks.
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