The highest-paid college president in the U.S. in 2014-15 was Jack P. Varsalona, who collected $5.4 million for 2014-15, his last full year at the helm of Wilmington University, a private, non-profit Delaware-based institution, with more than 21,000 mostly part-time students and no tenured faculty. 

That's according to the Chronicle of Higher Education's yearly review of presidents' pay, which nonprofit schools post in publicly-available IRS tax documents.

The University of Pennsylvania's Amy Gutmann, a prodigious half-billion-a-year fundraiser who last week agreed to stay on as head of the West Philadelphia-based school until 2022, was the fourth-best-paid U.S. college president, at $3 million, trailing Varsalona and top administrators at Washington University in St. Louis and Southern Methodist University.

Bosses at Columbia, Northwestern, Belmont, Chicago, Trinity (Conn.) and Cornell round out the Top 10.

Varsalona's compensation was swollen by a "one-time payment under the retention and retirement plan," triggered when the 30-year Wilmington U employee hit age 65, spokesman Joseph P. Aviola told me.

Varsalona was paid $1.5 million in salary and deferred comp the year before.  Aviola wouldn't say what Varsalona's successor, La Verne Harmon, will collect this year.

Wilmington U, backed by DuPont Co. heir Irenee du Pont and other prominent Delawareans, embraces a service-company-like business model, in which the top administrator is paid like the CEO of a medium-sized private corporation, while most of the school's 1,000-plus teaching staff consists of part-time adjunct faculty, who collect a few thousand dollars per course per semester.

Varsalona has told me this frees him to hire experienced nurses, engineers and other professionals as instructors, by the course, including people he knows in Delaware state government and companies.

He says his instructors are enthusiastic to teach what they know, satisfying education consumers -- the students, parents and employers who pay for college, often with government loans.

The school says it consistently boosts its annual enrollment, while many other private schools in the Northeast have found it tough to fill classes.  According to Aviola, enrollment has doubled since Varsalona became president in 2005-6, after nearly 20 years on staff. The endowment is $78 million, up from $13 million when he took the top job.

Wilmington University has a campus, offices and athletic team facilities near New Castle, Delaware, and other permanent and temporary classroom sites around Delaware and at high schools in South Jersey, plus online courses.

Last year Wilmington said it will build another campus west of U.S. 202 near the Pennsylvania state line, between Wilmington and West Chester. Aviola said the school expects to break ground on that project in the Spring.