CHAPEL HILL — Another study comparing college football players’ graduation rates to those of their student peers, another giant gap between the two.

Three years after the University of North Carolina’s College Sport Research Institute started tracking graduation rates based not on raw numbers but on how athletes performed when compared to other students, nothing has changed. Football players are still graduating about 20 percent less than regular students.

The latest edition of the study, planned for release Tuesday, found that FBS football players were 17 percent less likely to graduate than their male peers, down from 20 percent last year, with a three-year rolling average of 19 percent. At the FCS level, this year’s average was 8 percent, the three-year average 9 percent.

“We think this is really going to force schools to look at, philosophically, what they want to be the real purpose of college sports, and football specifically,” North Carolina professor Richard Southall, one of the study’s authors, said in a telephone interview Monday.

“We know that football is the revenue engine for everything. There may be players who come back and graduate, or leave in good academic standing, all of that stuff. But they are not receiving diplomas at the same rate as the full-time male population.

“Are these guys employees? And if they’re employees, then let’s pay them. If the purpose of them being there is to create revenue for all these other sports, do they need to be full-time students? Maybe they don’t.”

The ACC’s gap of 22 percent was among the highest in all of college football, behind only the Pac-12, but it’s important to note that because this measures the difference between football players and male students, that may have as much to do with how many regular ACC students successfully graduate as it does with football players not graduating.

With seven schools in the top 50 of the U.S. News & World Report rankings, the academic rigor of most ACC schools may skew the numbers, just as the influence of California and Stanford may affect those of the Pac-12.

Football actually shows a smaller gap than the most recent major-conference figures for baseball (31 percent) and men’s basketball (32 percent). But the studies do continue to raise the question of why more football players aren’t graduating in the ACC and elsewhere, and what needs to be done to fix that and make sure they get their degrees.

For the first time, the study broke graduation rates down by race this year, comparing black and white football players.

Across the board, black players graduated at lower rates than their white teammates, at the FCS and FBS levels – with the exception of the two Historically Black Colleges and Universities conferences, the MEAC and SWAC, where black football players graduated at higher rates than their white teammates.

Within the ACC, black football players had a graduation gap of 28 percent and white players 9  percent, gaps consistent in scope and proportion with other FBS conferences.

Southall said the latest data may spur further inquiry into tracking football players who are special admissions to universities, or examining the quality of the high schools football players attend.

At the least, it should encourage discussions about academic support for athletes, and football players in particular – especially on campuses tinged with scandal, including his own, where 64 percent of students in the suspect classes in North Carolina’s Department of African and Afro-American Studies were athletes.

“We need to have some open, frank discussions and see where this leads us,” Southall said. “You can do that, or you can deal with academic scandals every two years. Does it do anybody any good to say this was just some rogue individuals? ‘Two people at North Carolina, three people at Michigan, four people at Auburn, it’s not the system.’ We should be beyond that.”

DeCock: luke.decock@newsobserver.com, Twitter: @LukeDeCock, 919-829-8947