He may not know why, but I do, and so does everybody who’s followed Daniels in his nearly 20-year public career. He is notoriously tight with a dollar. Friends recall that as a beginning golfer, he played with a garden glove he already had instead of a store-bought, $3 golf glove. His parsimonious nature, when applied to public matters, is one reason he received more votes than any other officeholder in Indiana history in 2008, when he won reelection as governor, and it’s why he and his university—a 150-year-old land-grant school in West Lafayette, Indiana—are objects of curiosity and even wonderment in the world of higher education.

Most of the attention centers on that all-important number, 9,992. Not only is that the dollar amount an in-state student will pay Purdue for tuition and fees next year; it is also the amount such a student paid Purdue when Daniels became university president, in 2013. The university has also reduced the price of food services and textbooks. An undergraduate degree from Purdue, in other words, is less expensive today than it was when Daniels arrived.

Only when seen against the inflationary helix of American higher education can the singularity of this achievement be fully appreciated. The college-affordability crisis has become a staple of academic chin pulls, news stories, congressional hearings, and popular books written in tones of alarm and commiseration. From 2007 to 2017, the average annual cost of a degree at a four-year public university like Purdue rose from about $15,000 to more than $19,000—a jump of 28 percent after taking inflation into account. Only health care rivals higher education as an economic sector so consumed by irrational inefficiencies and runaway prices.

Read: Why is college in America so expensive?

The consequences are plain. Students and their parents have acquired debt totaling more than $1.5 trillion, more than all credit-card debt held in the U.S., and sufficiently large, according to the Federal Reserve, to be a drag on the economy. Roughly 70 percent of college students take out loans to finance their education. The average undergraduate leaves school more than $25,000 in debt.

At Purdue, by contrast, nearly 60 percent of undergrads leave school without any debt at all.

So how did Purdue do it?

“I always say it’s easier to explain what we didn’t do,” Daniels told me. “We didn’t try to get more money from the state. We didn’t shift from full-time faculty and fill the ranks with cheaper, part-time adjunct faculty. We haven’t driven up our percentage of international or out-of-state students,” who pay more than in-staters. Each of these measures has been taken up by other public universities, even as most have increased their in-state tuition.

Proud as he is of his number, Daniels worries that all the attention paid to the tuition freeze scants the improvements that the school says it has simultaneously made in educational quality and financial health.