This is a combination of all NHL data (regular season and postseason), 1970 through last night, grouped by the number of shots faced per game. I included "expected saves" based upon the season, opponent, and (where applicable) the postseason scoring environment. Given that there's almost 50 seasons worth of data, and that actual save percentages fluctuated wildly over that time, I'd focus on the relationship between actual save percentage and expected save percentage. This includes all games, even where a goalie was pulled or was a replacement - if a goaltender faced 10 shots in 20 minutes of play, then they are in the "30" category. My data currently does not have scoring by period, which would help to address the impact of score effects. I'm hoping to add that in at some point.