Plus-minus

Plus−minus (+/−, ±, plus/minus) is a sports statistic used to measure a player's impact on the game, represented by the difference between their team's total scoring versus their opponent's when the player is in the game. In ice hockey, it measures a player's goal differential. When an even-strength goal or shorthanded goal is scored, the plus–minus statistic is increased by one ("plus") for those players on the ice for the team scoring the goal; the plus–minus statistic is decreased by one ("minus") for those players on the ice for the team allowing the goal.Power play or penalty shot goals are excluded. An empty net does not matter for the calculation of plus–minus.

The statistic is sometimes called the plus−minus rating.

A player's plus−minus statistic is calculated for each game played, to provide a more meaningful measure over a full season. The statistic is directly affected by overall team performance, influenced by both the offensive and defensive performance of the team as a whole.

The NHL's Montreal Canadiens were the first team to track the plus−minus of its players, starting sometime in the 1950s. Other teams followed in the early 1960s, and the NHL started officially compiling the statistic for the 1967–68 season. While Emile Francis is often credited with devising the system, he only popularized and adapted the system in use by the Canadiens.

The NHL awarded the NHL Plus-Minus Award each year to the player with the highest plus−minus statistic during the regular season from 1982–83 to 2007–08.

The Western Hockey League (WHL) awards the WHL Plus-Minus Award each year to one of its players.

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