How to Assess Power Play and Penalty Kill Performance with Key Metrics

Think a 22 percent power play or an 85 percent penalty kill proves everything?
It doesn’t.
Those basic percentages are a start, not the verdict.
You need rate stats and process metrics — shots-per-60, goals-per-60, xG, formation time, GA/60 and PKY — to see whether the unit actually creates danger or just racks up numbers.
This post walks through the key metrics, shows what each one reveals (and what it hides), and gives clear signs to watch on tape so you can diagnose and fix both the power play and penalty kill.

Core Metrics to Evaluate Special Teams Efficiency

Basic percentage stats exist because they’re simple. A power play running at 22 percent sounds good until you watch the tape and see your guys chasing perimeter shots with zero net-front traffic. A penalty kill at 85 percent looks respectable, but what if your goalie’s posting a .950 save percentage while the defense gets shredded for forty shots an hour? Traditional percentages are starting points. They’re not answers.

Rate-based metrics fix some of that by tying events to time. Shots per 60 minutes on the power play tells you how many attempts your unit generates if it played a full hour. The math is easy: divide total shot attempts by total power play minutes, multiply by 60. Goals per 60 follows the same pattern. Conversion rate divides power play goals by total opportunities. These let you compare units with different amounts of ice time. A team with fifteen chances and three goals converts at 20 percent. A team with eight chances and two goals hits 25 percent, but the per-60 numbers show whether the second team actually created more danger in their limited looks.

• Power Play Percentage (PP%): Goals scored divided by total opportunities.
• Penalty Kill Percentage (PK%): One minus the ratio of goals allowed to times shorthanded.
• Power Play Conversion Rate: Power play goals divided by opportunities.
• Goals Against per 60 (GA60): Goals allowed per sixty minutes of shorthanded time.
• Shot Attempts per 60 (SA60): Total shot attempts allowed per sixty minutes shorthanded or generated per sixty on the power play.
• Formation Time Percentage: Seconds spent in an offensive formation divided by total power play seconds, times 100.
• Expected Goals (xG) on Power Play: Sum of shot quality estimates from location, type, and traffic across all power play attempts.
• Shorthanded Save Percentage (SHSV%): Saves divided by shots on goal faced while shorthanded.

Combining rate stats with event markers gives you process and outcome. A power play posting high shots-per-60 but low goals-per-60 signals either bad luck or terrible shot selection. Video and expected-goals models tell you which. A penalty kill allowing few shots per hour but bleeding goals? That’s either a goalie problem or catastrophic shot quality.

Advanced Analytics Framework for Power Play Assessment

Advanced analytics separate a power play that looks busy from one that actually threatens. Box scores count goals and shots. Process metrics tell you whether those goals came from repeatable structure or a puck bouncing off someone’s skate.

Power Play Process Indicators

Formation percentage measures how much of your power play time gets spent in a recognizable setup instead of regrouping at center or chasing loose pucks along the wall. Calculate it by dividing seconds in formation by total power play seconds, multiply by 100. A team spending 55 percent of power play time in formation generates more scoring chances than a team stuck in regroup mode half the advantage. Entry-to-formation conversion rate tracks how often a controlled zone entry leads to a set play. Time how long it takes from blue-line entry to first formation shot attempt, count how many entries never reach formation at all.

Shot-location heatmaps layer every power play shot onto a rink diagram, color-coded by frequency or danger. You see instantly whether your unit peppers the goalie from the point or generates looks from the slot and net front. Expected goals per 60 (xG/60) estimates shot quality by weighting location, shot type, traffic, rebound context. A power play generating 8.5 xG per 60 minutes with an actual goals-per-60 of 6.0 is probably due for positive regression. One posting 5.0 xG/60 with 7.0 goals per 60 is riding hot shooting that won’t last.

Comprehensive Framework for Penalty Kill Analysis

Goals against per 60 (GA60) measures how many goals your penalty kill surrenders if it played a full hour shorthanded. Shots against per 60 (SA60) and Fenwick against per 60 (FA60) track pressure. Scoring chances against per 60 (SCA60) isolates high-danger looks. Across full NHL seasons from 2008-09 through 2014-15, penalty kill percentage and GA60 correlated at 96.67 percent. Expected, since both metrics are built on goals allowed. The interesting finding is how weakly shot suppression predicts outcomes. SA60 versus GA60 correlated at only 20.21 percent. FA60 versus penalty kill percentage came in at 20.47 percent, rising to 24.31 percent when shortened seasons were excluded. SCA60 correlated even lower, around 17 percent against both GA60 and PK percentage. Suppressing shots helps, but the relationship is noisier than most coaches expect.

• Entry Denial Percentage: Percentage of opponent power play zone-entry attempts that are turned away at the blue line.
• Zone-Clear Rate: Number of successful exits from the defensive zone per shorthanded minute.
• Fenwick Against per 60 (FA60): Unblocked shot attempts allowed per sixty minutes shorthanded.
• Scoring Chances Against per 60 (SCA60): High-danger shot attempts allowed per sixty minutes shorthanded.
• Penalty Kill Save Percentage (PK Sv%): Goalie saves divided by shots faced while shorthanded.
• Rebound Control: Percentage of shorthanded saves that result in controlled possession or a zone clear rather than a second chance.

Goaltender variance complicates every penalty kill assessment. League-wide data shows PK percentage and shorthanded save percentage correlate at 67.3 percent. Goalie performance is the single largest swing factor. Meanwhile, SA60 and save percentage on the penalty kill correlate at less than 1 percent, FA60 versus save percentage sits near zero. Shot volume doesn’t predict whether your goalie will stop the puck. Chicago ranked first in penalty kill percentage one season despite middle-tier FA60 because two goalies posted elite save percentages shorthanded. St. Louis limited shot attempts better than almost anyone but finished mid-pack in PK percentage due to poor goaltending. Pittsburgh allowed the second-highest shots-against rate but thrived on strong saves. Minnesota and Vancouver both suppressed shots, but Vancouver’s two-goalie tandem pushed them higher in the rankings.

Using Penalty Kill Yield (PKY) to Measure Shorthanded Impact

Penalty Kill Yield measures net power play goals surrendered per game, accounting for shorthanded goals your team scores. The formula is PKY equals power play goals against minus shorthanded goals for, divided by games played. A team that allows thirty power play goals but scores six shorthanded goals across forty games posts a PKY of 0.600. They surrender a net of 24 goals, or 0.6 per game. Multiply PKY by 82 games to project full-season impact. A team with a PKY of 0.400 projects to allow 32.8 net power play goals over a season. A team at 0.500 projects to 41 goals. That nine-goal difference can swing playoff position.

Real examples from games through January 8, 2010 show how PKY reranks teams. The New Jersey Devils posted a PKY of 0.390, ranking third league-wide, while the St. Louis Blues came in at 0.488, eighth in PKY. The Blues ranked fourth in traditional PK percentage while the Devils sat tenth. The PKY gap of 0.098 projects to eight fewer net goals allowed by New Jersey over an 82-game season. Detroit posted 0.558 PKY, eleventh, versus Phoenix at 0.644, sixteenth. That 0.086 difference projects to seven goals across a full year, even though Phoenix ranked ninth in PK percentage and Detroit fifteenth. Dallas sat at 0.636 PKY (fifteenth) despite a 25th-ranked PK percentage, while Tampa Bay’s 0.786 PKY (26th) looked worse than their 18th-ranked PK percentage suggested. Dallas had surrendered five fewer net power play goals than Tampa in the season’s first half. Chicago ranked second in PK percentage and beat Boston’s first-place PK percentage on PKY by 0.054, equating to four or five fewer goals over 82 games.

PKY highlights penalty kill units that traditional percentage stats undervalue or overrate. A team that scores shorthanded goals regularly offsets power play goals against and limits the net damage from opponent advantages. When you’re assessing true penalty kill impact, net goals matter more than conversion rate alone.

Power Play Zone Entry and Formation Metrics for Accurate Evaluation

Zone entry efficiency determines how much of your two-minute advantage you spend attacking versus regrouping. Entry types include drop-pass carries, give-and-go exchanges, direct rushes. Conversion to formation time measures how many seconds pass from blue-line entry to the moment your unit sets up in a recognizable structure. Regrouping time is the inverse. Seconds spent backing out, resetting, chasing dump-ins. A power play that converts entries into formation quickly maximizes shooting windows. One that repeatedly regroups burns time without threatening the net.

Team case studies from full-season tracking demonstrate the entry-formation link. The Toronto Maple Leafs, tracked through 54 games, used drop-pass entries frequently and showed higher regrouping proportions than most teams. Controlled entries that required extra time to establish formation. The Montreal Canadiens found early success with an overload scheme, then declined when entry execution broke down and injuries removed a key forward. Stretches without that player aligned with poor power play performance. Around game 65, the Tampa Bay Lightning switched from a finesse approach to a screen-and-volume strategy. Shot attempts per 60 rose while formation time stayed flat. They generated more chances from the same setup time by prioritizing net-front traffic and rebound volume. The Washington Capitals posted elite entry efficiency around game 30 and nearly led the league in goals per 60 at five-on-four for the fourth straight season, but late injuries to a top defenseman degraded the unit. The New York Islanders spent less time in formation than most teams, logging high regrouping and out-of-formation proportions, which produced volatile shot totals and below-average goal rates until a late-season increase in both metrics despite low formation time.

Defensive Structure and Shot-Suppression Metrics on the Penalty Kill

Neutral-zone forecheck sits at the top of the penalty kill priority list because denying zone entry prevents the opponent from ever setting up. Teams that pressure puck carriers at the blue line force dump-ins, turnovers, offsides. Once the power play establishes offensive-zone possession, limiting shots and Fenwick becomes the next lever. Fenwick against per 60 (unblocked shot attempts) correlates most strongly with goals against among publicly available pressure metrics. It shows higher alignment to GA60 than shots on goal or scoring chances, especially across larger sample sizes. Entry denial is the most effective tactic, but most teams lack public microstat tracking, so FA60 serves as the best available proxy for offensive pressure once the opponent is in the zone.

Shot blocking, stick placement in passing lanes, zone-clear execution reduce dangerous chances after entry. A penalty kill that collapses into a tight box without active sticks allows perimeter Fenwick but bleeds high-danger chances from cross-ice seam passes. A kill that pressures the puck and blocks shooting lanes limits both shot volume and quality. Tracking successful exits, clears that result in controlled possession or icing, measures how often your kill escapes pressure before the opponent cycles into another dangerous look. Even with strong FA60 suppression, poor exit execution forces your goalie to face waves of chances and increases rebound opportunities for the attacking team.

Video-Breakdown and Event-Tagging Workflow for Special Teams Evaluation

Building a repeatable tagging system transforms video review from subjective opinion into objective data. You watch every power play and penalty kill shift, mark specific events with timestamps, code outcomes. Over time, those tagged events populate a database that feeds into per-60 calculations, formation percentages, trend analysis. The workflow starts with identifying which events matter most for predicting performance, then creating a simple tagging protocol that any analyst can follow consistently.

Key Events to Tag

Entry events include the method used to gain the offensive zone. Drop-pass carry, give-and-go exchange, direct rush, dump-and-chase. Timestamp the blue-line crossing and note whether the entry resulted in immediate formation, a regroup, a turnover. Formation markers record the moment your power play or the opponent’s power play establishes a recognizable setup (umbrella, overload, 1-3-1) and when that formation breaks down. Shot annotations capture location, shot type (wrist, slap, tip, one-timer), whether a screen or rebound was present. Personnel-change markers log line changes, injuries, tactical substitutions mid-advantage, especially when those changes align with performance shifts.

• Entry types: Drop-pass, give-and-go, rush entry, dump-in; timestamp blue-line crossing and outcome.
• Formation markers: Timestamp when structure is established and when it breaks; note formation type (umbrella, overload, etc.).
• Shot annotations: Location coordinates, shot type, presence of screen or deflection, rebound opportunity.
• Personnel change markers: Line changes, injuries, tactical substitutions; correlate with performance trend shifts.

Benchmarking Special Teams Against League Averages

League-average baselines show whether your power play or penalty kill over-performs or under-performs relative to the rest of the competition. Plot your team’s shot attempts per 60 and goals per 60 as solid lines, then add dotted horizontal lines representing the league median or mean for those metrics. If your power play SA60 sits above the league line and your G60 sits below it, you’re generating volume but lacking finish. If both lines run below league average, your process and outcomes both need work. Exclude games with zero power play or penalty kill opportunities from rolling-window charts to avoid artificial dips that distort trend analysis.

Adjusting for score effects and game state prevents misreading special teams performance. A team protecting a two-goal lead in the third period often plays more conservative penalty kills, allowing perimeter shots to run time off the clock rather than aggressively pressuring for clears. A trailing team might take more offensive-zone penalties, inflating their penalty kill opportunities but skewing per-60 rates. When you segment special teams metrics by score differential (trailing by one, tied, leading by one, leading by two-plus) you isolate whether strong numbers come from situational context or genuine system strength. Track whether performance holds steady across all game states or collapses when the score is close.

Home versus away trends and schedule density also influence special teams numbers. Some teams thrive on home power plays because they control line matchups after stoppages. Others struggle on the road when opponents deploy shutdown units. Long road trips or back-to-back games can degrade execution, especially on the penalty kill where skating and gap control demand high energy. Compare your team’s home SA60, G60, FA60, and GA60 to road splits. If road penalty kill performance drops sharply, fatigue or travel may explain more than tactical adjustments.

Integrating Player-Level and Goaltender Metrics into Special Teams Evaluation

Goaltender save percentage on the penalty kill drives results more than most coaches admit. Across multiple NHL seasons, PK percentage and shorthanded save percentage correlated at 67.3 percent. Meanwhile, shots against per 60 and save percentage showed almost no relationship. Less than 1 percent correlation. Fenwick against and save percentage sat near zero percent. What that means in practice: shot suppression helps, but goalie variance can override it. Chicago finished first in penalty kill percentage one season with middle-tier Fenwick against because two goalies posted elite save percentages shorthanded. St. Louis allowed fewer unblocked shot attempts than almost anyone but finished mid-pack in PK percentage due to poor goaltending. Pittsburgh survived the second-highest SA60 in the league by getting strong saves.

• Power play quarterback indicators: Primary assist rate, shot-assist rate, entry success percentage, formation-setup time.
• Screen-creation rate: Number of screened or tipped shots generated per 60 minutes of power play ice time.
• Entry-carrier success percentage: Controlled entries divided by total entry attempts for individual forwards or defensemen.
• Penalty kill stick-lane disruption percentage: Pass breakups and blocked passing lanes per 60 minutes shorthanded.
• Penalty kill block rate: Blocked shots per 60 minutes of shorthanded ice time, by player.
• Penalty kill clear rate: Successful zone exits per 60 minutes shorthanded, by player.

Personnel changes produce immediate and measurable shifts in special teams performance. The Philadelphia Flyers added a young defenseman (referenced as “Ghost” in tracking data) and saw instant upticks in both shot attempts per 60 and goals per 60 on the power play, even though their drop-pass entry scheme remained inconsistent. The impact was visible in the rolling five-game averages within a handful of games. Montreal’s power play declined sharply during stretches when a key forward was injured, and Washington’s late-season slump aligned with a top defenseman missing time. When you track player-level metrics (on-ice SA60, G60, entry success, formation efficiency) you can isolate which individuals drive results and which are replacement-level.

Turning Special Teams Analytics into Coaching and Practice Plans

Specific metrics point to specific drills. If your power play posts low formation percentage and high regrouping time, the problem is entry execution. Design small-area games that force quick decisions at the blue line. Two-on-two entry battles, where the attacking pair must gain the zone with control or regroup under pressure. Track entry success rate in practice and compare it to game numbers. If your penalty kill allows high FA60 but posts strong PK save percentage, you’re surviving on goaltending. Build drills that emphasize stick-lane coverage and shot blocking. Four-on-three keep-away where the penalty kill must disrupt passing seams, then transition to clears. Measure blocked shots and successful exits per rep.

Track improvement by comparing practice metrics to game performance over rolling windows. After two weeks of entry-focused drills, pull your power play’s five-game rolling SA60 and formation percentage. Did entry-to-formation conversion time drop? Did shot volume per opportunity rise? If the numbers move, the drill transfer is working. If they stay flat, adjust the drill constraints or increase competitive intensity. For penalty kill development, log FA60, clear rate, and GA60 across ten-game segments. When you see FA60 drop and clear rate climb without a corresponding drop in GA60, dig into goalie performance or shot quality allowed to find the remaining leak.

Final Words

We dove straight into core KPIs, like PP%, PK%, SA/60, GA/60, per-60 stats and PKY, and showed why rolling averages matter for noisy samples.

Then we added xG, formation percentage, heatmaps, video tagging, player and goalie indicators, and league benchmarks to find root causes and guide coaching choices.

Use this framework on how to assess power play and penalty kill performance: pick a few explanatory metrics, track them game-to-game, and build drills tied to those gaps. Keep measuring and you’ll see steady improvement.

FAQ

Q: What is the Gretzky rule in power plays?

A: The Gretzky rule in power plays is the “shoot early” idea — encourage quality quick shots, screens, and rebounds. It’s the coaching take on Gretzky’s “you miss 100% of the shots you don’t take.”

Q: How to calculate penalty kill percentage?

A: The penalty kill percentage is calculated as successful kills divided by times shorthanded, typically PK% = ((Times shorthanded − Power-play goals against) ÷ Times shorthanded) × 100.

Q: How is SOG tracked during a game?

A: Shots on goal are tracked by official scorers when a shot would have entered the net without the goalie’s save; blocked attempts, misses, and non-goal posts that don’t cross the line aren’t SOGs.

Q: What is the difference between a power play and a penalty kill?

A: The difference between a power play and a penalty kill is that a power play gives one team a man advantage to attack, while a penalty kill is the shorthanded team defending to prevent goals.