They're the pride and backbone of American higher education, doing essential research and educating en masse the next generations of scientists and engineers. But a new report argues the mission of the country's 101 major public research universities is imperiled by budget cuts amounting to one-fifth of their state funding over the past decade.

State support for public research universities fell 20 percent between 2002 and 2010, after accounting for inflation and increased enrollment of about 320,000 students nationally, according to the report published Tuesday by the National Science Board. The organization provides independent advice to the federal government and oversees the National Science Foundation.

Ten states saw support fall 30 percent or more and in two — Colorado and Rhode Island — the drop was nearly 50 percent. Only seven states increased support.