. . . . "and that 78% were post-pubescent." 

Where did you get that figure from? According to the report itself, 60 percent, the majority, were 13 and under. 73 percent were 14 and under. 

Something rarely taken into account is that onset of puberty has been going DOWN steadily for 100 years and has fallen by five years since 1920. This affects the time frame of the reporting period. In other words, from 1950 - 1980, when a lot of these cases occurred, the 13-year-olds and 14-year-olds may not have been pubescent. 

In 1950, onset of puberty in girls was 13.1; in 1980, it was 12.5. Researchers have confirmed that the same drop has occurred with boys, but onset for males is delayed by approximately one year. This means that the average onset of puberty in boys in 1950 would be 14.1. In 1980, it would be 13.5. This casts doubt on your thesis that 78% of the children in the JJ report were "post-pubescent."