Faculty salaries continued to increase this academic year, with the gap in salaries between public and private institutions also widening, according to a report by the College and University Professional Association for Human Resources (CUPA-HR).

Salaries at private institutions increased 3.7 percent, after rising 3.4 percent last year, while salaries at public schools increased 3.1 percent, the same percentage jump as last year, according to the report.

“Private institutions typically have greater flexibility in determining salary increase pools to allocate to faculty than do public universities,” said Andy Brantley, chief executive officer of CUPA-HR.

But Allison Professor of Economics Lawrence F. Katz, who studies labor economics, said that this trend is neither new nor surprising.

“That’s been true for a long time,” he said. “The public sector is much larger and covers a much larger range.”

Of the survey participants, 51 percent were from public institutions, while 49 percent were from private institutions. Harvard did not participate in this year’s study.

CUPA-HR staff members said that inflation was partly responsible for the rise in median salary.

“For the past two years, the trend has been pretty consistent that the overall increase in salary has been right on par with inflation or slightly above,” said Gayle Kiser, CUPA-HR director of communications.

The report also found that professors in engineering and the legal professions received the highest salaries at both public and private institutions.

At private universities, faculty members specializing in the library sciences received the lowest salaries, while professors at public universities in the english language and literature and letters departments received the lowest salaries.

Katz again said that this particular finding was not new.

There are “greater outside options for engineers and computer scientists,” he said. “It’s not surprising that university salaries reflect the broader salaries and economic forces.”

Katz also speculated that such a large differential between disciplines does not exist at Harvard.

“The gap at Harvard across disciplines is probably much smaller than these average trends,” he said. “Harvard has a long tradition of a more egalitarian wage structure.”

Around eighty-four percent of all U.S. doctoral institutions, 62 percent of master’s institutions, and 51 percent of bachelor’s institutions participated in the survey.