AKRON, Ohio - The University of Akron is paying more than $620,000 a year to former presidents, Luis Proenza and Scott Scarborough, who have remained on campus to teach following their tenure at the helm of the public school.

When presidents are hired, most are also awarded a tenured faculty position and their contract includes an option to teach when they are no longer president. The annual salary to teach is generally a percentage of their president's salary. At Akron it is 65 percent.

While many presidents leave for another job, it is not uncommon for those who retire to stay and teach, said Jeff Robinson, spokesman for the Ohio Department of Higher Education. But it is uncommon to have two former presidents teaching at the same time, he said.

Here's the background on Proenza and Scarborough.

Luis Proenza: Paid $325,000 a year.

Proenza, 73, stepped down on June 30, 2014 after 15 years as president.

He spread a one year sabbatical and $500,000 salary over two years and returned to campus in 2016 to teach.

Proenza, who lives in Vermilion, is teaching three honors colloquia for students in the Honors College this semester. They all meet on on Wednesday - from 12:05 to 1:45 p.m., 2:15 to 3:55 p.m. and 4:25 to 6:05 p.m.

Proenza retired as a professor of biology, but "he is more likely to concentrate on other areas of higher education, delivering lectures, participating in seminars, and teaching courses in various disciplines," the university said when he retired. "His credit hour load will be commensurate with that of a nine-month full-time tenured faculty member."

Each colloquia is two credit hours. Each student in the honors college must take three.

According to UA, the "standard load for all full-time faculty on nine-month contracts is 24 load credits per academic year and includes load credit for teaching, administrative responsibility, research/creative activity, institutional suport and service."

Proenza also receives a privately-funded $50,000 stipend each year for an endowed chair that has not yet been funded.

When Proenza announced his resignation in August 2013, trustees said they would lead an effort to raise $1 million to endow a trustees chair in higher education and the economy, modeled after Proenza's contributions to the university. Proenza was to be the inaugural chair holder on July 1, 2016.

Slightly more than $377,000 has been raised, spokesman Wayne Hill said. But Proenza is receiving the stipend, he said.

Proenza continues to be involved with the University of Akron Research Foundation when possible, Hill said. He represents UA as a distinguished fellow at the U.S. Council on Competitiveness and is a member of the Science, Technology and Economic Policy Board and co-chair of the Innovation Policy Forum at the National Academies of Science, Engineering, and Medicine.

"He has no specific future plans other than continuing in his current role and fulfilling his contract," Hill said in an email.

Scott Scarborough: Paid $292,500 a year

Scarborough, 55, has been a professor in the George W. Daverio School of Accountancy since fall 2016.

He is paid more than Ravi Krovi, dean of the College of Business Administration, who is paid $269,585 a year.

Scarborough is teaching four, three-credit hour classes this semester - two sections of Accounting Principles I, one section of Accounting Principles II and one section of Contemporary Federal Taxation.

He resigned in May 2016 after two tumultuous years as president.

Scarborough had the option of leaving UA and receiving his $450,000 salary for a year.

Instead he exercised an option in his contract to become a full-time faculty member and began teaching that fall.

Scarborough was paid his annual president's salary until Sept. 27, 2016. He then earned 65 percent of that salary.

Scarborough's contract said he will teach for a period of "not less than five years."

Much of Scarborough's early career was in financial management. He came to the University of Toledo in in 2007 as senior vice president for finance and administration and was senior vice president at the University of Toledo Medical Center. He was provost at UT when hired as president at UA.

What some other former presidents have done:

When Gordon Gee retired as Ohio State University president in July 2013, he stayed as president emeritus and a tenured law professor, earning $410,000 a year. He also was named director of the new Center for Higher Education Enterprise. He left in January 2014 to serve as interim president of West Virginia University and was later named president.

Former Kent State University President Lester Lefton moved to Los Angeles and formed an education consulting company when he retired in 2014.

When Cleveland State University President Michael Schwartz retired in 2009, he took a year's sabbatical then taught for two years.

This story was revised to reflect that each colloquia is two credit hours.