Tuition and fees at private U.S. colleges and universities will increase an average 4.3 percent for the 2009-2010 school year, the lowest percentage increase in at least 37 years, according to a survey to be released today, Bloomberg reported.

The average percentage increase is the same as in the 1972-1973 school year, when the National Association of Independent Colleges and Universities began its annual survey. The Washington-based lobbying group collected data from 350 colleges and universities.

Colleges, led by Harvard University in Cambridge, Mass., Dartmouth College in Hanover, N.H., and Stanford University near Palo Alto, Calif., are slashing spending and firing staff as endowments plunged as much as 30 percent in the last year. At the same time, schools curbed tuition increases because of the recession’s effect on families’ ability to pay, said Tony Pals, a spokesman for the association. Some private colleges with large endowment losses are likely to have larger tuition increases in the next two school years as budgets become further constrained, said John Isaacson, whose headhunting firm specializes in higher education.

Tuition and fees at private four-year colleges and universities in 2008-2009 averaged $25,143, a 5.9 increase from the year before, according to the College Board, the New York-based nonprofit that owns and administers the SAT test.

Private schools also increased the student financial aid for the coming school year, Pals said. The average increase in student aid provided by schools, called an institutional grant, was 9.2 percent, according to the survey. This is the first year the association collected student aid data.