Understanding Stats
PDO: The Number That Tells You Which Teams Got Lucky
PDO is a team's shooting percentage plus its save percentage. The league average is always 100. Teams significantly above it tend to fall; teams significantly below it tend to rise. It is the closest thing to a luck gauge hockey has.
PDO (named after a hockey analytics blogger, not an acronym) is one of the most useful and most misunderstood team stats in hockey. It combines two numbers: how often a team scores when it shoots and how often it stops shots when the other team shoots. Together they form a single indicator of whether a team's results are sustainable.
Why PDO averages 100
For every shot that becomes a goal, the shooting team gets a contribution to its Sh% and the opposing goalie gets a contribution to their GA%. The sum of all teams' shooting percentages and save percentages must balance out: every goal scored is also a goal allowed. This means across any full season, the average team PDO is always 100.
It is mathematically inevitable, not a coincidence. The implication is powerful: a team at PDO 103 is benefiting from unsustainable good fortune (scoring on an unusually high percentage of shots and stopping an unusually high percentage of opposing shots). Regression to 100 is the expected direction of travel.
Using PDO on JuniorPuck
PDO appears on the Teams page alongside xGF%, SF%, and GF/GA. Look for teams far from 100 in either direction. A first-place team at PDO 103.5 may be more vulnerable than their record suggests. A team sitting in fourth place at PDO 97.0 may be better than their record implies; they have been unlucky, and the numbers are likely to normalize.
Note
PDO is most useful in the first two months of the season when sample sizes are small and luck has outsized influence. By March, PDO has usually had time to partially normalize, and teams near 100 are showing truer performance.
What PDO is not
PDO is not pure luck. Good teams sustain PDO slightly above 100 because they consistently generate high-quality shots and have elite goaltending. The question is degree: a PDO of 100.5 might reflect real quality; a PDO of 104 almost certainly includes a meaningful luck component. The further from 100, especially early in a season, the more skeptically you should view the underlying record.