The vast income gap in college degrees, in 3 charts

Update and correction: Susan Dynarski and Matthew Chingos — two experts on the economics of higher education — have pointed out serious flaws with the Pell Institute report's methodology. It overstates the percentage of students from high-income families who earn a college degree, and particularly overstates the graduation rate for those students. In other words, while these charts are striking, they're probably wrong. The article below is the original. This article contains more information about why the charts are misleading, and what the actual college-going and graduation rates by income quartile are.

It's probably not surprising that kids from well-off families are more likely to get a college degree than their peers. But it's shocking just how big the gap is.

This chart shows the percentage of 24-year-olds with a bachelor's degree based on their family income. Of the top quartile, 77 percent eventually get a degree. In the bottom quartile, just 9 percent do:

The problem isn't only starting college. It's finishing. Going to college right after high school is a near-universal experience for high school graduates from the top quartile. Still, 45 percent of the bottom quartile goes to college, too:

When you look at how many of those college-goers earn a diploma, though, the disparities are truly stunning. This chart only looks at 24-year-olds who have attended college — it filters out those who never tried to go. And what you see is that for the richest quartile, enrolling in college makes graduation a virtual certainty.

For everyone else, it's at best a coin flip. More than half of students from the lower half of the income distribution aren't finishing college — even when they start.

This is why getting more students in the door through free tuition won't be enough.

Certainly some of those low-income students weren't academically prepared. Maybe college wasn't the right choice for every single one of them, and maybe some would be happier in a skilled trade. But that's almost certainly true for the wealthier students, too — and virtually all of them manage to get their degrees, "college material" or not. Students from the top quartile weren't pushed into a path to earn a two-year degree or a certificate, to become a well-compensated plumber or truck driver.

Figuring out what's stopping their low-income peers, and removing those roadblocks, is a pressing question for higher education.

(All charts are from the Pell Institute for Opportunity in Higher Education, whose recent report has much more on these issues.)

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