A rising tide does not automatically lift all boats, especially if you’re an African-American college student, a new report shows.

Even at public colleges that have improved their graduation rates, the gap between blacks and whites is growing wider, not narrower, in more than half of cases. The report examined 232 four-year public colleges where graduation rates had improved over a 10-year period.

Written by researchers at The Education Trust, a nonprofit group that advocates for closing achievement gaps, Rising Tide II: Do Black Students Benefit as Grad Rates Increase? found that while college graduation rates for black students did increase overall between 2003 and 2013, the gap between blacks and whites also increased. At 30 percent of the colleges examined, black graduation rates declined or stagnated as white grad rates climbed. The study’s authors argue that the difference between colleges that widened the gap and those that narrowed it lay not in dissimilar student enrollments, but in different actions taken by the institutions to address the gap.

“Even among the institutions that improved, black students were not always able to reap the benefits,” said Andrew Nichols, Education Trust’s director of higher education research and data analytics and a co-author of the report. “What we see in our report lends credibility to what the student activists have been saying. You can think it’s anecdotal when it’s just a protest here and there, but what we find here are distributing trends that have been taking place for years and years.”

Related: Black students are drastically underrepresented at top public colleges, data show

Dr. Nichols noted that not all the findings were bad. At 70 percent of the college where overall graduation rates improved, black students made progress as well — just not as much progress as their peers.

The report singles out universities that have made progress. For example, at Ohio State University, 73 percent of black students graduated in 2013, up 26 percentage points since 2003. While 83 percent of white students there graduate, the gap between the two groups has shrunk nine points over that time period. The university credits initiatives aimed at supporting first-generation students as well as black and Latino students. One program begins in middle school and provides academic and financial support through college. There are also programs and retreats led by students themselves to provide ongoing support and problem solving.

At Texas Tech University, black student graduation rates have risen by ten percentage points, and the gap between black and whites students has shrunk by four points. After noticing a high dropout rate among students of color, college administrators developed a program called Mentor Tech. It includes about 60 workshops a year that offer academic, career and personal support to black and Latino students. Still, the report’s authors note that even some of the colleges making the most progress have a long way to go – the average graduation rate for black students at Texas Tech, for example, was 53 percent in 2013.

Related: College degree gap grows larger between whites, blacks and Latinos

The report also lists the institutions that are doing the worst. For example, at Texas A & M University-Commerce, only 29 percent of black students graduated in 2013, a drop of 13 percentage points since 2003. The gap between black and white students has risen a whopping 23 points.

Nichols says change has to start from the top, and the diversity of colleges where there has been improvement shows what’s possible.

“It’s not just about the students you bring in. It’s what you do with them,” he said. “You can’t just blame the kids.”

[Cross-posted at The Hechinger Report]

Meredith Kolodner

Meredith Kolodner is a staff writer. She previously covered schools for the New York Daily News and was an editor at InsideSchools.org and for The Investigative Fund at the Nation Institute. She’s also covered housing, schools, and local government for the Press of Atlantic City and The Chief-Leader newspaper and her work has appeared in the New York Times and the American Prospect. Kolodner is a graduate of Brown University and Columbia University’s Graduate School of Journalism and an active New York City public school parent.