David Swensen, who spent more than three decades managing one of the world’s best performing college endowments as Yale University’s chief investment officer, has died of cancer, the university said.

“David served our university with distinction. He was an exceptional colleague, a dear friend, and a beloved mentor to many in our community. Future generations will benefit from his dedication, brilliance, and generosity,” Yale President Peter Salovey said in a statement.

He was 67 and was first diagnosed with cancer in 2012.

Over three decades Swensen helped the university’s endowment grow to $31.2 billion, making Yale one of the world’s richest universities. The endowment helps fund salaries and financial aid.

Salovey said Swensen “revolutionized” institutional investing by shifting the university’s money into less liquid asset classes and helped prepare a new generation of investors who have gone on to lead other large endowments.

Swensen, who earned a Ph.D. in economics from Yale, returned to his alma mater in 1985 after having worked on Wall Street for several years. He took a significant pay cut to lead the investment office and found an endowment valued at $1 billion.

By focusing on a long time horizon, Swensen pioneered investments in hedge funds, private equity and real estate, creating an investment model now known as the “Yale Model.”

His record is one of the most admired in the industry. Yale returned 9.9% a year over the 20 years ending June 30, 2020, while other college and university endowments earned an average 5.6% return. In 2000, when the tech bubble burst, Yale’s endowment posted a 41% return, thanks largely to a hedge to dampen its exposure to technology investments.

Swensen also trained a new generation of investors in his classes at Yale and in the investment office who went on to lead endowments at Princeton, Massachusetts Institute of Technology and Stanford.

“In addition to his transformational impact, David was generous in sharing insights and guidance,” Mohamed El-Erian, who once ran Harvard University’s endowment, wrote on Twitter.

On Monday, Swensen and his long-time colleague Dean Takahashi taught the last class of the term for “Investment Analysis”, a seminar they taught for 35 years, Yale’s Salovey said in the statement.