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Student debt is worsening wealth inequality between white and black Americans. That's the takeaway from a new study titled, "Racial Disparities in Student Debt and the Reproduction of the Fragile Black Middle Class," published this year in the journal Sociology of Race and Ethnicity. The researchers found that black young adults take on 85 percent more education debt than their white counterparts — and that disparity compounds by 7 percent each year after the borrowers leave school, because African-Americans face unique repayment challenges.

To be sure, student loan repayment is an issue across the board. Fewer than half of all borrowers have paid even $1 toward the principal of their balance five years into repayment, according to the Education Department. But for black borrowers, the situation is even grimmer. White borrowers pay down their education debt at a rate of 10 percent a year, compared with 4 percent for black borrowers. As a result, 15 years after they leave college, black adults hold 185 percent more in student loans than white adults. "The racial wealth gap is both the biggest and has grown the fastest among those with a college education," said Jason Houle, assistant professor of sociology at Dartmouth College and co-author of the study. "We point to student loan debt as potentially one thing that explains why that's happened." The study data were drawn from the National Longitudinal Study of Youth 1997 Cohort, a nationally representative sample of over 8,900 respondents who were interviewed nearly every year since. The researchers calculated that student debt contributed to nearly a quarter of the black-white wealth gap, shown below.