Only a small percentage of private colleges have already seen enrollment “significantly affected” during the economic downturn, but leaders at many institutions have substantial concerns about those numbers dwindling in the future, according to a report released Thursday by the National Association of Independent Colleges and Universities.

NAICU’s survey, which was completed by about 370 institutions, is the latest in a series of efforts by the association to assess the financial stability of its membership. As was the case with its most recent survey, NAICU found that college leaders are still relatively uncertain and pessimistic about the future.

Despite fears about what lies ahead, fewer than 7 percent of respondents said they’d already seen enrollment significantly affected, when asked as late as December 12. But the specter of enrollment declines is a chief concern, and fears of such dips were pronounced in the surveyed group.

“For [a] tuition-driven institution with 86 percent of its revenue tied to enrollment-based measures, a decline in enrollment is our greatest financial concern,” one respondent commented.

Nearly 57 percent of colleges surveyed expect some level of enrollment decline as early as spring. But the range of expected decline varies greatly. Just under half of the institutions expect “a slight decrease,” but that category ranged from 1 percent -- slight to the point of negligible -- to 10 percent -- not necessarily so slight.

Despite a barrage of news stories about student loan availability tightening up, only about 7 percent of the responding colleges said loan availability for their students was “significantly affected" at this point. Nearly 31 percent said they’d seen no effect at all.

Not surprisingly, given the well-publicized free fall in the stock and other investment markets, there was great consensus among college leaders that endowments are suffering. Of those surveyed, nearly 68 percent said their endowments were significantly affected.

Faced with endowment losses, one respondent gave this gloomy prediction: “We have taken years to build [the endowment] with gifts and careful investment; to see it decline so quickly and put us back five years is a hazard which puts significant pressure on raising tuition when families can afford it least -- this trend will make education available [only] to the affluent.”

A number of institutions have employed cost-cutting measures, but it's unclear whether those colleges have already seen resources depleted significantly or are merely taking prudent steps in uncertain times. Here are some of the steps the surveyed colleges have already taken:

• 4.6 percent have frozen tuition.
• 8.4 percent have frozen or cut student aid budgets.
• 49.9 percent have frozen hiring.
• 7.3 have cut academic programs.
• 15.6 percent have laid off staff.
• 10.5 percent have laid off faculty.