Joseph Bronski's excellent 2021 book "An Empirical Introduction to Youth" points out that 50 years ago Tanner showed most young people finishing puberty at 14 or 15 years of age

Tanner was METICULOUS as hell

Tanner links:

https://sci-hub.se/10.1136/adc.44.235.291

&
https://sci-hub.se/10.1136/adc.45.239.13