All kinds of entities have suffered downgrades from credit rating agencies in recent months, and now universities are on the hot seat, The Wall Street Journal reports.

The drop of colleges’ investment portfolios has made it difficult for them to pay their bills.

Both Moody’s and Standard & Poor’s pulled their triple-A rating for Dartmouth College down a level last week.

They acted because of investment losses for the school’s endowment and its need to issue bonds.

Moody’s has downgraded 20 universities this year and has a negative outlook for another 55.

"That's comparable to the rate of downgrades universities saw during the dot-com bust," Moody's Managing Director John Nelson tells The Journal. "And we probably will surpass it."

While Harvard University has maintained its triple-A rating, it and Yale may have to reduce their investment allocations to hedge funds and private equity, superstar bond fund manager Bill Gross said at a conference covered by Bloomberg.

That’s because those investments are too risky.

“The Yale and Harvard portfolios, which have succeeded enormously over the past 10 or 20 years in terms of the emphasis on illiquidity and private investments and risk-taking — you have to question that model,” says Gross, co-chief investment officer at PIMCO.

The two Ivy League schools devoted over 50 percent of their endowments to hedge funds, private equity, real estate and commodities as of June 30.

Harvard’s endowment lost 22 percent between last June and December, while Yale’s fell 25 percent.