When Chatham College hired its president back in 1991, one might have argued that the odds for an extended stay weren't great.

Lake Fong, Post-Gazette Chatham College President Esther Barazzone chats with Megan Thomas, left, and Mariah Hinkle, both 17 and students of West Mifflin High School, at the 12th annual Girls and Women in Sports luncheon at Chatham College on Friday. Click photo for larger image. Related coverage Graphic: The American College President Graphic: Classroom path to the presidency Harvard taps first woman as president

Given the eat 'em up, spit 'em out nature of a college presidency, it seemed only a matter of time before fund-raising and enrollment worries, an angry donor or some other job pressure would take its toll.

Yet 15 years and two fund-raising campaigns later, Esther Barazzone, 60, continues to guide the 1,600-student women's college. And she's by no means the only survivor.

A report due out today says the nation's college and university presidents are holding their jobs longer than at any time since the mid-1980s. Though considerable turnover continues, the average sitting president has served 8.5 years, up from 6.6 years in 2001 and 6.3 years in 1986, when the American Council on Education first conducted its survey, the largest of its kind.

The trend has pushed the average age of a sitting president to just shy of 60, raising the possibility of a significant exodus during the coming decade, the report's authors say.

Just down the road from Chatham, University of Pittsburgh Chancellor Mark Nordenberg, 58, is in his 12th year running the vast research school. Jared Cohon, who was 49 when he was hired to lead Carnegie Mellon University, is closing in on a decade in the president's office.

At Penn State University, Graham Spanier, 58, will mark his 12th year as president in September.

All four have already served longer than their immediate predecessors.

Theories abound on what's behind the upswing nationally, from more generous compensation packages to increasingly dynamic institutions that are making it harder for presidents to walk away from their jobs.

"One factor could be that governing boards are trying to keep their presidents longer, to facilitate multiyear fund-raising campaigns, to allow enough time to realize the vision that comes from long-range planning," Dr. Spanier said.

At Penn State, the specter of octogenarian Joe Paterno coaching the football team could be yet another motivator.

"Compared to a football coach I know, I'm just getting warmed up," Dr. Spanier said.

In the five national surveys prior to 2006, the average presidential tenure always fluctuated between six and seven years. Even those involved in preparing the latest survey were searching for an explanation.

"We're not sure of the reason why it has jumped up," said Jacqueline King, director of the center for policy analysis with the Washington, D.C.-based association, an umbrella organization representing 1,600 colleges and universities.

If anything, she said, "the job has become more demanding."

The study, "The American College President," is based on information from 2,148 public and private college and university presidents. It provides a snapshot of current officeholders, their experiences and how they came to the job.

Even though Harvard University has named its first female president in its 371-year history, the flow nationally of women and minorities into the top college spot has slowed of late, the study found.

In fact, the typical president remains a white man, married, with a doctorate, who served previously as a provost or chief academic officer. The largest share, 54.2 percent, are Protestant.

Women account for 23 percent of the presidencies, more than double the 9.5 percent share in 1986, but only 2 percent more than in 2001. Minorities account for 13.6 percent of the nation's college presidents, up from 12.8 percent in 2001 and 8.1 percent in 1986.

Male presidents were significantly more likely to be married than female presidents -- 89 percent versus 63 percent. Fourteen percent of female presidents were divorced, compared with 4 percent of their male counterparts.

Since 1986, the average age of a president has crept upward, from 52.3 years to 59.9. Forty-nine percent of presidents are at least 61 years old, up from 14 percent in 1986.

Much was made in the 1990s of the arrival of presidents from outside higher education. But the survey found that the trend apparently has peaked at 15 percent. The share who were previously full-time faculty stands at 69 percent, compared with 75 percent 20 years ago.

The study says, increasingly, presidents who are being picked have executive-level backgrounds, usually in academic affairs. Once presidents are in office, the job's rapidly expanding demands push many of them away from direct oversight of areas such as academics and more toward external constituencies, including donors and state legislators.

Dr. Spanier, who heads a system of two dozen campuses and nearly 84,000 students, said he still sees plenty of turnover among his peers. There have been 30 presidents within the Big 10 during his tenure, and among the Association of American Universities, an elite group of research schools, he is one of only 13 who have served longer than 10 years.

But he has no plans to step down.

"Although the job is increasingly demanding and complex, I feel I have the best job in higher education and hope to continue for several years to come," he said.

At Chatham, campus support for two fund drives totaling about $50 million fueled building and other projects that have helped to define Dr. Barazzone's tenure. She said she's been fortunate to have a board that over the years has resisted temptation to overreact to down periods of fund raising or enrollment.

"Boards can easily churn their presidents and blame them for fund-raising or enrollment problems and not look to all the pressures from the outside world," she said.

Dr. Barazzone said her own school has had to transform itself to stay competitive, and the changes have kept the job fresh. Half of Chatham's enrollment is now in graduate programs, and the school has added doctoral degrees, online programs and, in September, confirmed it was seeking state approval to become a university.

"Colleges and universities have become much more entrepreneurial and dynamic places," she said. "I think those presidents who have stayed longer are ones who have gotten engaged in very dynamic situations. I'm having a wonderful time."