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linkApparently, following the 2006 season, the NFL changed its rules to allow each team control of their own footballs. This rule change was made at the urging of some of the league's top quarterbacks, like Brady and Manning:
Then, starting in the 2007 season, with the new rule in place, New England suddenly became very good at avoiding fumbles. These histograms show number of offensive plays per fumble for New England compared to the other 31 teams in the league. From 2007 onwards, the team became insanely good at avoiding fumbles, compared to every other team.: