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Home-field advantage (HFA) is the inherent benefit each team has when playing in their home stadium. In the NFL, a rough estimate of seasonal HFA can be calculated by differentiating point totals between the home-team and the visitor; last season, league-wide HFA settled near 1.7 points. The...
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Bottom line: overall, regular season HFA has been under 3 points for 1-2 decades, and has been between 1-2 points lately. It was negative (i.e. visiting teams outscored home teams) in 2019-2020.