If you are among the fortunate few who grow up poor and manage to earn a bachelor’s degree, you might reasonably expect your earnings potential to rise by the same proportion as that of other people who earn a bachelor’s degree. Your actual level of earnings may not match others, but the percentage increase, relative to a high school diploma, ought to be comparable. This is certainly the case in terms of gender and race. Many economists assume this pattern holds for those from different backgrounds in terms of income, too.

But it turns out that the proportional increase for those who grew up poor is much less than for those who did not. College graduates from families with an income below 185 percent of the federal poverty level (the eligibility threshold for the federal assisted lunch program) earn 91 percent more over their careers than high school graduates from the same income group. By comparison, college graduates from families with incomes above 185 percent of the FPL earned 162 percent more over their careers (between the ages of 25 and 62) than those with just a high school diploma: