He hit 37 HRs in just 123 games, finishing 2nd to Ryan Braun's 41. Stanton also set the all-time record for most HRs in a season by a Panoramian (yes, all-time!) His SLG was .608 while his AVG was .290. That gives him an isolated power (ISO) of .318, which, as I will show below, is outstanding for a player his age.
But Marlins Park was not a good HR park this year. 113 HRs were hit there (by both teams) while 157 were hit in Marlin road games. So there were only 72% as many road HRs as at home. It is only one year, but that is a low HR park factor.
Stanton's ISO at home was .287 while on the road it was .357. He had 16 HRs at home in 247 ABs while on the road it was 21 in 202 ABs. I can't help wondering how he would do in a fair park. I don't know how symmetric Marlins Park is, so maybe righties were not hurt as much as lefties. But he has a big home/road differential.
The table below shows the top seasons in ISO relative to the league average
by players who were 22 or younger who had at least 400 PAs. Williams gets 252 because .329/.130 = 2.52. That gets multiplied by 100
The rest of the top 15 include Bob Horner, Mel Ott, Jimmy Sheckard, Juan Gonzalez and Joe Jackson. So Stanton is in great company.
Stanton is one of just 3 guys to have an ISO of at least .275 in 2 different seasons at age 22 or younger. The next table shows all those seasons.
Other players with season of .250 or higher were Alex Rodriguez, Juan Gonzalez, Hal Trosky, Frank Robinson, Vladimir Guerrero, Bob Horner, Evan Longoria, Darryl Strawberry. Jimmie Foxx, Mel Ott, Joe DiMaggio and Ted Williams each had one more .250+ season to go along with those seen in the table.
Here are all the players who had 2 seasons of 30+ HRs at age 22 or younger