In an effort to position itself as affordable in an era of rising student debt, Portland State University unveiled a guarantee that students who are extremely on the ball will be able to graduate in four years - or get any fifth-year classes for free, The Oregonian reported.

Wim Wiewel, president of the university said participating students "will have the sources and the advising they need to graduate in four years."

However, the pledge comes with many caveats.

Students have to declare a major at the start of freshman year, pass a full load of 45 credits every year, earn decent grades and refrain from changing majors, adding minors and switching campuses.

Graduating in five or six years or more -- not four -- is the norm at the university, state figures show. Just 17 percent of students who started at PSU as full-time freshmen in 2006-07 graduated in four years. But the graduation rate reached 45 percent after six years, the state reported.

About half of PSU transfer into the school midway through their college years after earning an Associate's Degree or about half of their credits at Portland Community College or another community college.

Those students won't be eligible for the four-year guarantee, the Oregonian reported.

The University's Provost Sona Andrews acknowledged the plan also won't work for many PSU students who start there as freshmen because they need to work to pay for school or support families and can't attend full time all year.

Andrews said the guarantee will benefit students who don't sign up for the guarantee because it will put more of the onus on the university to offer essential college courses student's need, when they need them.

Under this plan, the university is tasked with giving students a clear path to graduation within four years for all majors.

According to the Oregonian, Many universities in other states already offer such a pledge. It does not appear that huge numbers of students sign up for the guarantees or remain eligible, given the requirements to stick with a major and complete a full load of classes, said Brian Prescott, director of policy research at the Western Interstate Commission for Higher Education.

The pledge's guarantee could help a university compete for students whose parents want assurances they won't get caught with an expensive fifth year of tuition, room and board, and who like the idea that an adviser will carefully watch over the student's progress each term, he said.