Harvard University's endowment suffered investment losses of at least 22% in the first four months of the school's fiscal year, the latest evidence of the financial woes facing higher education.

The Harvard endowment, the biggest of any university, stood at $36.9 billion as of June 30, meaning the loss amounts to about $8 billion. That's more than the entire endowments of all but six colleges, according to the latest official tally.

Harvard said the actual loss could be even higher, once it factors in declines in hard-to-value assets such as real estate and private equity — investments that have become increasingly popular among colleges. The university is planning for a 30% decline for the fiscal year ending in June 2009.

Other university endowments also are suffering, and many states are cutting public funding of higher education. Colleges are instituting hiring freezes, planning enrollment cuts and discussing steep tuition increases, intensifying worries about the impact of the recession and financial crisis on college access.

The federal government already has taken emergency steps to boost lending to students, and several well-off colleges have said they will maintain or boost financial aid to help families hurt by job losses, investments setbacks and borrowing problems. But not all colleges have the financial heft to withstand the many forces bearing down on them.

Joni Finney, a professor at the University of Pennsylvania who studies college economics, says she worries that public universities and less-wealthy, smaller private colleges may not be able to keep their doors open to all students. "If you go down the food chain of higher education, it's harder and harder to deal with these kinds of cuts," she says.

Private-college budgets are sensitive to investment declines because they typically tap their endowments each year to help cover operating expenses.