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.
Notable players (NHL)
Only four players have been multiple single-season leaders for the plus−minus statistic: defenseman Bobby Orr led the league six times, Wayne Gretzky led the league four times, while John LeClair and Chris Pronger were two-time leaders.
Since the NHL started tracking the plus−minus statistic in the 1967–68 season, the top achievements have been:
Top 5: Season high
- Bobby Orr, 1970–71, +124
- Larry Robinson, 1976–77, +120
- Wayne Gretzky, 1984–85, +100
- Dallas Smith 1970–71, +98
- Guy Lafleur, 1976–77, +89
- Steve Shutt, 1976-77 +89
Top 5: Career high
- Larry Robinson, career, +722
- Bobby Orr, career, +582
- Ray Bourque, career, +527
- Wayne Gretzky, career, +520
- Bobby Clarke, career, +507
Top 3: Season low
Top 3: Career low
Top 2: Single game high
There are some drawbacks to the traditional calculation of the plus–minus statistic. Not all types of goals are included, specifically power play goals. Every goal included in the calculation is weighted the same regardless of the situation - even strength, power play, short-handed or empty net. Also, plus–minus is not applied to goaltenders.
Situational plus–minus (Sit +/-) is an alternative calculation that takes into account all types of "team-based" goals, which excludes only penalty shot and shootout goals. Each goal is weighted based on the number of skaters (i.e. not goaltenders) on the ice. The plus–minus rating is calculated by dividing the number of skaters on the ice for the team scored upon by the number of skaters on the ice for the scoring team, applied as a plus to all players (including goaltenders) on the ice for the scoring team and as a minus for all players on the ice for the team scored upon (including goaltenders).
The situational plus−minus statistic has recalculated the NHL plus–minus statistic going back to the 2009–10 season, for which the top achievements have been:
NHL Top 5: Season high (since 2009–10)
- Alex Ovechkin, 2009–10, +87.71
- Nicklas Backstrom, 2009–10, +74.05
- Daniel Sedin, 2010–11, +73.63
- Brayden Point, 2018–19, +72.77
- Nikita Kucherov, 2018–19, +69.64
NHL Top 5: Season low (since 2009–10)
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.
A plus−minus statistic has been used in sports economics to analyze the degree of competitive balance over time in association football.
- Fitzpatrick, Jamie. "What is the "plus–minus" statistic and how is it calculated?". About.Com.
- The Plus and Minus of Plus-Minus - LCS Hockey
- "Learn More". PlusMinusLine.com. Retrieved 2019-11-24.
- "PlusMinusLine | National Hockey League Situational Plus/Minus". PlusMinusLine.com. Retrieved 2019-11-24.
- Lewis, Michael (2009-02-13). "The No-Stats All-Star". The New York Times.
- Sittl, Roman; Warnke, Arne Jonas (2016). "Competitive balance and assortative matching: Data from the German Bundesliga". VoxEU.org.