Yale University’s endowment posted a 3.4 percent gain on investments for the fiscal year ended June 30, the school said Friday, outperforming Harvard University’s 2 percent loss.

Yale, based in New Haven, Conn., ended the year with $25.4 billion in assets, down slightly from $25.6 billion a year ago. That’s after delivering about $1.2 billion to the university’s operating budget.

Over 10 years, Yale posted an average annual return of 8.1 percent, compared with Harvard’s 5.7 percent gain. Its endowment is second by assets among higher education institutions, after Harvard’s $35.7 billion fund.

Yale, which farms out most of its assets to third-party managers, beat the public markets over the past decade, something its Ivy League rival, which relies on a mix of internal and outside managers, failed to do.

Investing in a portfolio of 60 percent US stocks and 40 percent bonds would have produced a 6.9 percent gain.

BETH HEALY

GLOBE STAFF

Beth Healy can be reached at beth.healy@globe.com. Follow her on Twitter @HealyBeth.