young.
Do we really expect adults who are 18 and included in these kinds of data sets to be wealthy? Almost 7% of all US citizens are in college right now (counting full and part time)... Do we expect them to have high salaries?
Yet when the far left compare large data sets regarding income inequality, they don't control for age. They compare the income of these students to the income of a 65 year old and say that there is injustice in the US between the rich and pour.
(note that of course there is income inequality in the US - I think we just need better data analysis of the issue)