The salaries of American public university presidents soared as inflation fell last year, according to a survey by the Chronicle of Higher Education. The new data, published Monday, showed that the median pay for public university heads rose to $428,000 in 2014, a rise of nearly 7 percent over the previous year and almost four times the salary of full-time professors.

The latest numbers come at a time of rising tuition fees and falling inflation. According to the Center on Budget and Policy Priorities, the average annual tuition fee at four-year public institutions rose almost 30 percent between 2008 and 2015. After spiking in 2009, inflation remained stubbornly above 1 percent until 2014, when it sank to 0.8 percent. The year 2015 is expected to see slight deflation, according to the U.S. Inflation Calculator.

The Chronicle of Higher Education surveyed 238 presidents and chancellors across 220 public universities and colleges. 

Pennsylvania State's Rodney Erickson topped the ranking, making almost $1.5 million in total compensation for 2013-2014. Erickson stepped down from his post last year.

Six out of the ten leaders who received the highest in total compensation left in either 2013 or 2014, earning at least part of that money through generous severance packages.

“In the context of overall college budgets, these are minimal expenditures,” Chronicle of Higher Education database reporter Sandhya Kambhampati told SFGate. She added that universities across the country are trying to lure more high-value leaders with greater pay packages.

"There's a finite number of people and retaining them is pretty difficult, so as a result of that, they have to pay their presidents what's competitive," Kambhampati told the Houston Chronicle.

Since 2010, nine public college leaders have earned over $1 million. However, that amount is dwarfed by the pay of private university officials. The Chronicle of Higher Education found that 36 private college heads were paid over $1 million in 2012, the latest data available, CNN reported.