system
A chat on subreddit /r/me_irl
human
I remember reading a study and it's like 1-2% of the population iirc. 12 inches exists but it is like 0.000 something%

The vast majority of men are between 4 and 7 inches.

Don't ask for the source, I read this article in high school but hopefully someone knows lol
gpt
1-2% is much too high for 9", try something between 1 in 1000 to 1 in 10,000. Self reported sizes on the internet are often lies/fakes or improperly measured. They do exist, but are not nearly as common as they appear to be online.

Anything over 10 basically doesn't exist, as much as wishful thinking on the internet might like to believe otherwise.