Posted by Hans Van Slooten on December 9, 2014
We've added four new measures to goalies on Hockey-Reference.com, Games Started, Quality Starts, Quality Start Percentage, Really Bad Starts. These should be available anywhere you see goalie stats on the site currently, including the Play Indexes.
Games Started (GS) should be fairly obvious, this is the number of games that a goalie started (i.e. did not come in for another pulled goalie).
Quality Starts and Quality Start Percentage were developed by Rob Vollman, and are described in his Hockey Abstract. Here is a brief description, but we encourage you to pick up a copy of his book for additional discussion of this statistic (and many others):
A Quality Start (QS) is when the goalie achieves at least the mean save percentage (for the season) in a game. For the 2013-2014 season that percentage is 91.5%. So, if Tuukka Rask allows only 2 goals on 28 shots (a 92.9% save percentage), that is considered a Quality Start. There is an additional criteria for low shooting games: if a goalie faces 20 or fewer shots, he only needs to get an 88.5% save percentage. The relationship between save percentage and winning percentage (and hence the definition of Quality Start) is shown here (prior to 2009-2010):
|Save %||Win %|
|0.913 or better||0.777|
|0.900 to 0.912||0.536|
|0.885 to 0.899||0.503|
|0.884 or worse||0.246|
Quality Start Percentage (QS%) is simply the number of Quality Starts / Games Started. This gives you a sense of how often the goalie has a Quality Start. A good rule of thumb for this stat is that anything less than 50% is bad, anything over 60% is among the league leaders, and the league average for an NHL regular is about 53.4%. Also, according to Vollman: "Based on the average of every goalie with fewer than ten starts in a season, the average for replacement -level goalies is 42.8% but, in fairness, there is some selectino bias involved in this since playing that poorly will generally limit you to ten start in the first place."¹
Really Bad Starts (RBS) is another stat coined by Vollman that is "awarded" whenever a goalie has a save percentage in a game less than 85%. A team only has a 10% chance of winning when the goalie has save percentage that low.
Where to find these new stats
"So," you are asking, "where do I find these new stats?" They are available anywhere goalie stats have been listed on the site. Due to a limitation of our data source, they are only available going back to the 2007-08 season. So, if you go to a goalie page, you'll see the stats listed in the NHL Standard and NHL Playoffs sections.
Additionally, you can see the league-wide stats on the yearly page for a league. For instance, the 2015 stats are available here.
As always, we welcome any feedback.