The Washington Capitals made it into the NHL playoffs last night after a 2-1 win over the Philadelphia Flyers. Fans have observed the Caps huge negative goal differential–the difference between the total number of goals the team has scored and the number of goals they have allowed–as a rarity for playoff teams. And when you look closer at the data, that is certainly the case.
I downloaded a decade’s worth of NHL standings data from ESPN and calculated each team’s total points as a share of possible points (2013 was a lockout year and 2020 and 2021 were COVID years, so those seasons had fewer than the usual 82 games played) and their goal differential. You can clearly see the positive correlation between winning (points percentage) and goal differential, with the Caps a clear outlier. You can explore the data below and I’ll update it tomorrow after the final set of games are played tonight.
