That seems too broad of an age range since you end up comparing 34 year old high school graduates to people with undergraduate degrees a decade earlier in their

That seems too broad of an age range since you end up comparing 34 year old high school graduates to people with undergraduate degrees a decade earlier in their careers. Only looking at the first few years of a career for undergraduates has another problem I mentioned in a different comment. Not all professions have high starting salaries even if your lifetime earning potential is significantly improved. As far as I can tell this methodology, if applied to graduate degrees, would conclude medical school isn't worth it as an example.