This is in support of Eric T.’s work today over at NHL Numbers. He adjusted a regression scatter plot, but I think you could also group age and age+1 seasons of 20+ GP (n=
912 930) and run a 50-performance rolling average through age compared to percent of change in save percentage. Not only does this suggest that there’s progression followed by fall-off after about 33 or so, but also that very young goaltenders are incredibly volatile in their performance. A 100.1% change in SV% from this chart, incidentally, would be like going from .900 to .901 (goes without saying, but maybe someone wants to see that).