Moody's Investors Service downgraded 34 higher education institutions in 2012 while upgrading only 3, the ratings agency reported Friday, an indicator of ongoing financial challenges facing colleges and universities. Analysts chalked up the downgrades to problems raising net tuition revenue, continued state budget cuts, and enrollment troubles. "Of the seven public universities whose ratings were downgraded in the fourth quarter, five had declines in total full-time equivalent student enrollment," the report notes. Prominent downgrades included the Pennsylvania State System of Higher Education and Pennsylvania State University.