The number of minorities in college has increased substantially in recent years, but not fast enough to keep up with demographic changes.

As a result, U.S. adults in their late 20s are reaching only about as far as the age group immediately above them in terms of educational attainment. And among Hispanics, a lower proportion has completed at least an associate’s degree when compared with those age 30 and older.

Unless the trend is reversed, the increases in Hispanic participation in higher education won’t be enough to ensure that a growing proportion earn a college degree.

The findings are highlighted in a biennial report to be released Thursday by the American Council on Education, supported by the GE Foundation.

“One of the core tenets of the American dream is the hope that younger generations, who’ve had greater opportunities for educational advancement than their parents and grandparents, will be better off than the generations before them,” said council President Molly Corbett Broad. “Yet this report shows that aspiration is at serious risk.”