What Is Plus/Minus in Hockey?
Plus/minus is one of the most fundamental—and most hotly debated—statistics in ice hockey. At its core, plus/minus measures a player's goal differential while they are on the ice during even-strength and short-handed situations. In other words, it tracks how many goals their team scores minus how many goals the opposing team scores while that specific player is on the ice.
A player receives a plus (+) each time their team scores an even-strength or short-handed goal while they're on the ice. Conversely, they receive a minus (-) each time the opposing team scores an even-strength or short-handed goal while they're playing. The sum of these plus and minus events creates their plus/minus rating for the season, a game, or any defined period.
How to Read a Plus/Minus Number
Understanding how to interpret plus/minus ratings is straightforward. A player with a +25 rating means their team scored 25 more goals than the opposition during even-strength and short-handed play while they were on the ice. A player with a -15 rating means the opposing team outscored their team by 15 goals during the same situations.
The scale ranges from significantly negative (indicating a player whose team struggles when they're on the ice) to significantly positive (indicating a player whose team thrives during their ice time). For context, an elite defenseman or forward on a strong team might finish a season with a rating between +20 and +50, while a player on a struggling team might finish between -20 and -40.
| Plus/Minus Rating | Interpretation | Typical Player Type |
|---|---|---|
| +40 or higher | Exceptional; elite player on strong team | Star forwards/defensemen |
| +20 to +39 | Very good; strong contributor | Regular starters |
| 0 to +19 | Average to above-average; balanced | Solid players |
| -1 to -19 | Below average; team struggles with player | Depth players, struggling teams |
| -20 to -39 | Poor; significant liability | Benchwarmer or weak team player |
| -40 or lower | Extremely poor; major concern | Struggling player or failing team |
How Is Plus/Minus Calculated in Hockey?
The calculation of plus/minus appears simple on the surface, but the rules contain important nuances that many fans overlook. Understanding these rules is essential to interpreting the statistic correctly.
The Even-Strength Rule
The primary scenario for plus/minus calculation occurs at even strength, meaning both teams have the same number of players on the ice (typically 5-on-5). When a team scores an even-strength goal, all players on the ice for the scoring team receive a plus, and all players on the ice for the opposing team receive a minus.
For example, if the Dallas Stars score a goal while playing 5-on-5 with players A, B, C, D, and E on the ice, each of those five players receives a +1. The five opposing players on the ice at that moment each receive a -1. This happens repeatedly throughout a season, and the cumulative total becomes a player's plus/minus rating.
Short-Handed Goals and Special Situations
The rules become more complex when special teams situations enter the picture. Short-handed goals—goals scored by a team that is numerically disadvantaged (playing with fewer players due to a penalty)—also count toward plus/minus. If a team scores while short-handed, all players on the ice for that team receive a plus, and all opposing players receive a minus.
However, power play goals and penalty kill situations introduce critical asymmetries that many people don't realize:
- Power play goals: If a team scores a goal while on a power play, only the players on the ice for the scoring team receive a plus. The opposing players on the ice do NOT receive a minus, because they were already numerically disadvantaged.
- Penalty kill goals: Conversely, if a team scores a short-handed goal while killing a penalty, both the scoring team and the opposing team's players on the ice receive credit (plus for the scoring team, minus for the opposing team).
- Empty-net goals: When a team pulls their goalie for an extra attacker and scores an empty-net goal, the attacking team receives a plus. However, the defending players on the ice receive a minus, even though they were trying to score themselves (an unusual situation where defensive players get penalized for the opposing team's offensive success).
| Situation | Scoring Team Gets Plus | Opposing Team Gets Minus |
|---|---|---|
| Even-strength goal | Yes | Yes |
| Short-handed goal | Yes | Yes |
| Power play goal | Yes | No |
| Empty-net goal | Yes | Yes |
| Penalty kill goal | Yes | Yes |
| Power play goal against | No | Yes |
These rules create the first major flaw in plus/minus: a player can be punished for situations beyond their control. A defenseman pulled to the ice for an empty-net attempt receives a minus if the opposing team scores, even though they were there to help their team score, not to defend.
Where Did Plus/Minus Come From? A Brief History
Plus/minus didn't emerge overnight as an official NHL statistic. Its history reveals how the league's approach to player evaluation has evolved—and why some statistics persist long after their usefulness has been questioned.
The Early Days (1960s-1970s)
The origins of plus/minus trace back to the early 1960s, when coaches and general managers began using it internally as an evaluation tool. Scotty Bowman, the legendary coach who would go on to become one of hockey's greatest minds, first started tracking plus/minus while coaching the Montreal Junior Canadiens in the Ontario Hockey Association during the mid-1960s. Bowman believed the concept came from Toe Blake, the Montreal Canadiens' head coach, who was using the metric with the professional club.
The statistic made intuitive sense to coaches: it offered a simple way to measure whether a player's team was outscoring opponents during their ice time. In an era before computers and advanced analytics, this was a valuable shorthand for evaluation.
However, the NHL did not formally track plus/minus as an official statistic until 1963, though online historical data is only available from the 1967-68 season onward. Interestingly, even after the league began collecting the data, general managers insisted it remain confidential. The statistic was not distributed to the media or published in the league's weekly statistical sheets. This secrecy lasted over a decade, suggesting that even the league's decision-makers had reservations about the statistic's reliability.
Public Release and Early Criticism (1975)
The turning point came in August 1975, when the NHL finally released plus/minus statistics to the public alongside standard box score statistics. The decision to publish remains somewhat mysterious—no official explanation has been documented—but the media's reaction was swift and skeptical.
Charles Halpin, writing in the August 1975 edition of Hockey News, immediately challenged the statistic's validity. Halpin noted a fundamental flaw that remains relevant today: "The top teams have the best plus players and the worst teams have the most minus performances." In other words, a player's plus/minus rating says more about their team's overall quality than their individual performance.
Halpin went further, questioning why the league had kept the statistic confidential for so long if it was truly revelatory. He concluded his critique with a prescient observation: "Hockey fans have been wondering about the game's plus and minus figures for a long time. After reading them for the first time in the Hockey News they may go on wondering for many more years."
His skepticism proved justified. Nearly 50 years later, hockey analysts are still debating whether plus/minus deserves a place in player evaluation.
Awards and Recognition (1983-2008)
Despite the early criticism, the NHL decided to celebrate plus/minus excellence. In 1983, the league introduced the Emery Edge Award, given annually to the player with the best plus/minus rating (minimum 60 games played). The award was named after Emery Edge, a hockey personality, and represented the league's official endorsement of the statistic.
Notable Emery Edge Award winners included:
- Bobby Orr (1970-71): +124—the highest plus/minus in NHL history
- Wayne Gretzky (1984): +85
- Pavel Datsyuk (2007-08): +41
However, hockey writers remained skeptical. In 1986, Globe and Mail columnist Neil Campbell wrote, "Only a marketing expert could come up with a trophy like the Emery Edge Award. A real hockey man would recognize it as what it is—an individual award that arises from a team accomplishment." Campbell's critique highlighted a key weakness: plus/minus conflates individual skill with team success.
The award underwent several iterations, eventually being sponsored by companies like Alka-Seltzer and Budweiser. However, the NHL discontinued the trophy after the 2007-08 season, when Pavel Datsyuk earned the final Bud Light Plus-Minus Award. The discontinuation signaled growing recognition that the statistic was not a reliable measure of individual excellence.
Why Is Plus/Minus So Controversial in Hockey?
If plus/minus is so flawed, why has it persisted in hockey for over 60 years? The answer lies in its simplicity—and in the fact that its flaws are so fundamental that they've spawned decades of debate.
The Team Dependency Problem
The most glaring criticism of plus/minus is that it is fundamentally dependent on team quality. A player on a championship-contending team will accumulate a high plus/minus simply because their team scores more goals than it allows. Conversely, a player of identical skill on a struggling team will post a negative plus/minus.
Brian Burke, President of Hockey Operations for the Calgary Flames, famously called plus/minus "the most useless statistic ever devised." His reasoning was blunt: "If your team stinks, so does your plus-minus. And it's compounded if you play against the opposition's top players."
Consider two hypothetical players:
- Player A plays for a dominant team that outscores opponents 4-2 on average during his ice time. His team's system is strong, his goaltender is elite, and his linemates are skilled. Result: +35 plus/minus.
- Player B plays for a weak team that is outscored 3-4 on average during his ice time, despite playing an identical role. His team's system is poor, his goaltender is average, and his linemates are less skilled. Result: -28 plus/minus.
These ratings tell us far more about the teams than about the individual players. Yet plus/minus ratings are often used to compare players across different organizations—a methodologically flawed approach.
Luck and Variance in Plus/Minus
Beyond team quality, luck plays a significant role in plus/minus. Hockey is a sport where small variations in shooting percentage, save percentage, and bounces can dramatically affect outcomes.
A player might be on the ice for a goal that results from a fortunate deflection or a goaltender's mistake—neither of which reflects the player's individual performance. Over a full season, these random variations should theoretically balance out, but in any given season, luck can skew plus/minus significantly.
Additionally, team shooting percentage and save percentage are largely outside any individual player's control. If a team's forwards are unusually good at scoring, every player on that team benefits with a higher plus/minus. If the team's goaltender is having an off year, every player suffers with a lower rating.
The Deployment Factor
Coaches make strategic decisions about which players face which opponents. A player matched up against the opposition's third line will accumulate a higher plus/minus than a player consistently deployed against the top line, all else being equal.
Ice time distribution is another crucial variable. A player who receives 25 minutes per night has more opportunities to accumulate plus/minus points than a player receiving 10 minutes. Over a full season, volume matters enormously.
Furthermore, team systems and coaching philosophies affect plus/minus. A team that plays a defensive, low-scoring system will naturally produce lower plus/minus ratings for its players, even if the team is successful. Conversely, a team that plays a high-pace, offensive system will generate higher plus/minus ratings, regardless of whether the team is actually effective at preventing goals.
What Are the Main Limitations of Plus/Minus?
Beyond the controversies outlined above, plus/minus has several structural limitations that make it unreliable as a standalone evaluation metric.
Doesn't Measure Defensive Skill Alone
One of the most persistent myths about plus/minus is that it measures defensive reliability. In reality, plus/minus measures net goal differential—a blend of offensive and defensive contribution. A forward who scores 40 goals but allows 50 goals while on the ice will have a negative plus/minus, despite being an elite scorer. Conversely, a defenseman who prevents 30 goals but allows the team to score only 20 while on the ice will also have a negative rating.
This conflation of offense and defense makes it impossible to isolate a player's defensive contribution using plus/minus alone. A player might have a negative plus/minus not because they're a poor defender, but because they're paired with a weak linemate, play against elite competition, or play for a team with poor offensive depth.
Ignores Quality of Competition
Plus/minus treats all goals equally, regardless of context. A goal scored against an elite team's top defensive line is weighted the same as a goal scored against a struggling team's third line, even though the latter is far more impressive defensively.
This creates a systematic bias: players on strong teams face weaker competition on average (because top players are concentrated on fewer teams), while players on weak teams face stronger competition. Yet plus/minus penalizes the latter group more severely.
Excludes Power Play and Special Teams Impact
As discussed earlier, plus/minus excludes power play goals and penalty kill situations. This is a massive gap, because special teams can account for 20-30% of a team's goal differential in a season. A player might be an elite power play performer or penalty killer, but their plus/minus rating won't reflect this contribution.
| Metric | What It Measures | What It Misses |
|---|---|---|
| Plus/Minus | Even-strength and short-handed goal differential | Power play impact, penalty kill impact, shot quality, possession |
| Corsi | Possession (all shots, including blocked shots) | Quality of shots, goaltending, luck |
| Fenwick | Possession (unblocked shots) | Shot quality, goaltending |
| Expected Goals (xG) | Shot quality and likelihood of scoring | Actual results, goaltending performance |
| Corsi For % | Possession share | Actual goal outcomes |
How Does Plus/Minus Compare to Modern Hockey Statistics?
The limitations of plus/minus became increasingly apparent as hockey analytics evolved. Modern statistics attempt to address plus/minus's flaws by focusing on different aspects of player performance.
Plus/Minus vs. Corsi
Corsi measures shot attempts (all shots, including blocked shots) while a player is on the ice. The theory is that shot volume is a better proxy for team dominance than goal differential, because it's less affected by luck and goaltending.
A player with a +15 Corsi For % means their team attempted 15% more shots than the opposition during their ice time. This is considered more stable and predictive than plus/minus, because it's based on a larger sample size (there are far more shots than goals in hockey) and is less susceptible to variance.
Why Corsi is superior to plus/minus:
- Less affected by luck (larger sample size)
- Accounts for shot volume, not just results
- More predictive of future success
- Less dependent on goaltending
Plus/Minus vs. Fenwick
Fenwick is similar to Corsi but excludes blocked shots, measuring only unblocked shot attempts. The logic is that blocked shots represent team defense, not individual player performance, so they should be excluded from an offensive metric.
Fenwick is generally considered more reliable than Corsi for measuring offensive impact, because it isolates the shots that actually reached the goaltender.
Plus/Minus vs. Expected Goals (xG)
Expected Goals (xG) represents the quality of shot attempts, not just the quantity. Each shot is assigned a probability of resulting in a goal based on historical data (distance from goal, angle, type of shot, etc.). A shot from the slot might have a 0.10 xG value, while a shot from the point might have a 0.02 xG value.
xG is superior to plus/minus because it:
- Accounts for shot quality, not just results
- Is less dependent on luck
- Predicts future goal-scoring better than plus/minus
- Isolates individual player contribution from goaltending
| Statistic | Sample Size | Luck Dependence | Predictive Power | Ease of Understanding |
|---|---|---|---|---|
| Plus/Minus | Low (goals only) | High | Moderate | Very high |
| Corsi | High (all shots) | Low | High | Moderate |
| Fenwick | High (unblocked shots) | Low | High | Moderate |
| Expected Goals | High (quality-adjusted) | Very low | Very high | Low |
Real-World Examples: How Plus/Minus Affects Players
While plus/minus's limitations are well-documented, its real-world impact on players' careers and contracts is undeniable.
Success Stories: High Plus/Minus Ratings
Bobby Orr's +124 rating in the 1970-71 season remains the gold standard for plus/minus excellence. Playing for the dominant Boston Bruins, Orr was on the ice for far more goals than his opponents scored. This extraordinary rating reflected both his elite individual performance and his team's dominance.
Other notable high plus/minus seasons include:
- Wayne Gretzky, 1984-85: +85 (Edmonton Oilers)
- Larry Murphy, 1988-89: +85 (Calgary Flames)
- Al MacInnis, 1990-91: +82 (Calgary Flames)
These players were all on elite teams and were themselves elite performers, but it's impossible to disentangle their individual contribution from their team's quality using plus/minus alone.
Cautionary Tales: When Plus/Minus Misleads
Patrick O'Sullivan's -35 rating in 2009-10 is perhaps the most famous cautionary tale. Playing for the cellar-dwelling Edmonton Oilers, O'Sullivan had the league's worst plus/minus. However, this rating said far more about the Oilers' organizational dysfunction than about O'Sullivan's individual ability.
O'Sullivan later reflected on the impact: "It was one of the things that really hurt me for the rest of my career." The stigma of the worst plus/minus in the league followed him, despite the fact that he was not uniquely responsible for the Oilers' failures.
Other examples of misleading plus/minus ratings include:
- Players on playoff teams with negative plus/minus: A strong defensive player on a weak team might have a -15 rating, while an average player on a strong team might have a +25 rating, despite the defensive player being more valuable.
- Elite forwards on weak teams: A 50-goal scorer on a last-place team might have a -20 plus/minus, while a 20-goal scorer on a first-place team might have a +30 rating.
The Bonus Clause Reality
Despite plus/minus's questionable reliability, it still appears in player contracts. The NHL's collective bargaining agreement includes "Schedule A bonuses" for entry-level contracts, which include ice time, goals, assists, points, points per game, and plus/minus.
In recent years, even high-profile signings have included plus/minus bonuses. For example, Artemi Panarin's entry-level contract with the Chicago Blackhawks included a plus/minus bonus, not because the organization believed it was the best metric, but because it was simpler to include all Schedule A bonuses rather than negotiate exceptions.
These financial incentives mean that players have a direct interest in their plus/minus rating, even if the statistic is flawed. This creates perverse incentives: a player might avoid playing against top competition or seek to be benched during games where their team is trailing, to protect their plus/minus rating.
Should Hockey Fans Still Care About Plus/Minus?
Given all the criticisms and limitations outlined above, is plus/minus worth paying attention to at all? The answer is nuanced.
When Plus/Minus Is Useful
Trend analysis over time: Plus/minus can be useful for identifying trends. If a player's plus/minus declines significantly from one season to the next, it might indicate declining performance, changes in team quality, or shifts in deployment. However, this should be combined with other metrics.
Team-level analysis: Plus/minus is more reliable when applied to entire teams rather than individual players. A team's cumulative plus/minus directly correlates with its goal differential, which is the best predictor of wins.
Context-dependent comparison: Comparing players within the same team, in the same season, can provide some insight. Two forwards on the same team, with similar ice time and deployment, might have different plus/minus ratings that reflect actual performance differences.
When Plus/Minus Misleads
Comparing players across teams: Using plus/minus to compare a player on a strong team to a player on a weak team is methodologically flawed.
Evaluating individual defensive skill: Plus/minus alone cannot determine whether a player is a strong defender.
Predicting future performance: Plus/minus is less predictive of future success than advanced metrics like Corsi or xG.
Ignoring context: A player's plus/minus rating without knowledge of their team quality, linemates, deployment, and role is essentially meaningless.
The Future of Plus/Minus in Hockey Analytics
The trajectory is clear: plus/minus is gradually being replaced by more sophisticated metrics. The NHL has embraced advanced statistics, and front offices increasingly rely on Corsi, Fenwick, xG, and other metrics that better isolate individual player performance.
However, plus/minus will likely persist in hockey culture for years to come, simply because it's easy to understand and has been around for so long. Casual fans will continue to reference it, and contract bonuses will continue to include it, even as sophisticated analysts move beyond it.
The future belongs to metrics that can answer more specific questions: "How much does this player contribute to shot generation?" (Corsi/Fenwick), "How good is this player at creating high-quality chances?" (xG), and "How does this player perform relative to replacement level?" (WAR-style metrics).
Frequently Asked Questions About Plus/Minus
Q: Can a player have a plus/minus of zero?
A: Yes. A player with a plus/minus of zero means their team scored and allowed an equal number of goals during even-strength and short-handed situations while they were on the ice.
Q: Does plus/minus count power play goals?
A: Power play goals count for the team that scores them but not for the opposing team. If Team A scores a power play goal, the Team A players on the ice receive a plus. The Team B players do not receive a minus, because they were numerically disadvantaged.
Q: Why do some players have very high plus/minus ratings?
A: High plus/minus ratings typically result from a combination of elite individual performance and team quality. A star player on a dominant team will accumulate a high rating, but it's impossible to separate how much is due to the player versus the team.
Q: Is plus/minus a good way to evaluate defensemen?
A: Plus/minus is a poor way to evaluate defensemen alone, because it conflates offensive and defensive contribution. A defenseman might have a negative plus/minus despite being an excellent defender, if their team's forwards don't score enough goals.
Q: What's the difference between plus/minus and goal differential?
A: Goal differential is a team statistic (the difference between goals scored and allowed across an entire season). Plus/minus is an individual statistic (the difference between goals scored and allowed while a specific player is on the ice).
Q: Has anyone ever had a plus/minus higher than Bobby Orr's +124?
A: No. Bobby Orr's +124 in 1970-71 remains the NHL record. The second-highest is Wayne Gretzky's +85 in 1984-85.
Q: Do coaches still use plus/minus to evaluate players?
A: Yes, coaches use plus/minus as one of many evaluation tools, typically to identify trends over blocks of time (10 games, a month, etc.). However, most modern coaching staffs also rely on advanced metrics.
Q: Can a goaltender's plus/minus be calculated?
A: Goaltenders are not assigned plus/minus ratings in the traditional sense, because they're on the ice for all goals (both for and against). However, some advanced metrics like Goals Saved Above Average (GSAA) serve a similar purpose for goaltenders.
Q: Why hasn't the NHL eliminated plus/minus if it's so flawed?
A: Plus/minus persists because it's simple, has historical precedent, and appears in player contracts. Additionally, eliminating it would require renegotiating collective bargaining agreements with the players' union.
Q: What should I use instead of plus/minus to evaluate players?
A: Advanced metrics like Corsi For %, Fenwick For %, Expected Goals (xG), and player-tracking data provide more reliable insights. However, no single statistic tells the whole story—context and watching games remain essential.