Teenagers are still children. They don't have developed brains. Also take into account that teenagers are growing up more slowly than they did in the past. It is not disingenuous to put them together in the same statistic.
Commenter below mentions that the statistic used is Americans under the age of 18. They are not adults mentally or legally. They are children.
Mine is worse on the left. Maybe we can combine our ears and have the ability to hear things fully again!