That study is worthless. It takes no account of differences in education levels, career choice, etc.

My Dad was a career Air Force man and afterward went to school to learn Accounting. I went to school for an Engineering degree directly after High School. So my earnings are going to be higher.

So what about my son? If decides to skip College, ruling out a best selling book, making it big in acting or sports, or some amazing invention, there is no way he can earn more than I do. Although if he chooses to go to College, it will not guarantee a good salary. It depends on career path. He has hinted at a degree in Mathematics. If he teaches, forget about a good salary. If he gets an advanced degree and does research in cyrptology, bingo! He has vast earning potential.