Plus−minus (+/−, ±, plus/minus) is a sports statistic used to measure a player's impact on the game, represented by difference between their team's total scoring versus their opponent's. 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.
While the statistic officially measures a difference, it is sometimes (inaccurately) referred to as the plus−minus ratio or plus−minus rating.
While a player's plus−minus statistic is calculated for each game played, it tends 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.
Notable players (NHL)
Only four players have been multiple single-season leaders for the plus−minus statistic: defenceman Bobby Orr led the league six times, Wayne Gretzky led the league four times, while John LeClair and Chris Pronger were two-time leaders.
Top 5: Season high
- Bobby Orr, 1970–71, +124
- Larry Robinson, 1976–77, +120
- Wayne Gretzky, 1984–85, +98
- Dallas Smith 1970–71, +94
- Guy Lafleur, 1976–77, +89
Top 5: Career high
- Larry Robinson, career, +730
- Bobby Orr, career, +597
- Ray Bourque, career, +528
- Wayne Gretzky, career, +518
- Bobby Clarke, career, +506
Top 3: Season low
Top 3: Career low
Top 2: Single game high
Although the statistic was pioneered in the sport of hockey, it has found its way into use in other sports and areas of life. For instance, the NBA's Houston Rockets first utilized a modified version of the stat, which helped reveal the unheralded effectiveness of light-scoring Shane Battier. It is now in regular use throughout the NBA.
- Fitzpatrick, Jamie. "What is the "plus–minus" statistic and how is it calculated?". About.Com.
- The Plus and Minus of Plus-Minus - LCS Hockey
- Lewis, Michael (2009-02-13). "The No-Stats All-Star". The New York Times.