Statistics

In hockey statistics is a set of commonly used arithmetic formulas that supposedly give useful insight into the overall on-ice performance of the players. How useful they are varies greatly and is subject to debate.

Common statistics:

1. Corsi, called shot attempts (SAT) by the NHL, is the sum of shots on goal, missed shots and blocked shots. It is named after coach Jim Corsi, but was developed by an Edmonton Oilers blogger and fan who developed the statistic to better measure the workload of a goaltender during a game. Corsi is used to approximate puck possession – the length of time a player’s team controls the puck – and is typically measured as either a ratio (like plus-minus) of shot attempts for less shot attempts against, or as a percentage. According to blogger Kent Wilson, most players will have a Corsi For percentage (CF%) between 40 and 60. A player or team ranked above 55% is often considered “elite”.
2. Fenwick, called unblocked shot attempts (USAT) by the NHL, is a variant of Corsi that counts only shots on goal and missed shots; blocked shots, either for or against are not included. It is named after blogger Matt Fenwick and is viewed as having a stronger correlation to scoring chances.
3. PDO, called SPSV% by the NHL, is the sum of a team’s shooting percentage and its save percentage. PDO is usually measured at even strength, and based on the theory that most teams will ultimately regress toward a sum of 100, is often viewed as a proxy for how lucky a team is. According to Wilson, a player or team with a PDO over 102 is “probably not as good as they seem”, while a player or team below 98 likely is better than they appear. PDO is not actually an acronym for anything. It comes from the online handle of Brian King, the first to propose it, for forums and Counter-Strike.
4. Zone starts is the ratio of how many face-offs a player is on for in the offensive zone relative to the defensive zone. A player who has a high zone start ratio will often have increased Corsi numbers due to starting in the offensive zone, while a player with a low zone start ratio will often have depressed Corsi numbers. Strategically, coaches may give their best offensive players more offensive zone starts to try and create extra scoring chances, while a team’s best defensive players will typically have more defensive zone starts. The use of zone starts in analysis has decreased. It has been determined that “on-the-fly” shifts account for more than half (58%) of all shifts.