First of all, I'm not so much interested in raw salary as I am with net worth. If Sociologist Jane at 45 years old makes $50K, and pays $10K in loans each year,

First of all, I'm not so much interested in raw salary as I am with net worth. If Sociologist Jane at 45 years old makes $50K, and pays $10K in loans each year, is she better off than Plumber Joe who makes $35K a year, owns his house, and earns $10K in dividends. How bout 20 years later? Your statistics are also assuming that it is the college degree itself that is producing the difference in income, and not the individual. As politically incorrect as it is to say, a good portion of the non-bachelor degree population would not earn much anyway - 'urban' with minimal basic education, immigrants without language skills, low IQ, disabled, etc. Find me a study based on IQ - one in which similarly intelligent persons are matched on income (not salary) at varying ages, and I'm guessing that in the future, many in the middle IQ range will not benefit from their liberal arts degree.