Dr. Glenn Lang recommends everyone read the Commonfund Higher Education Price Index (HEPI). You can download a copy of the PDF from their website.
HEPI has been calculated every year since 1983 and includes inflation data going back to 1961. Since fiscal year 2002, HEPI has been based on a regression formula. HEPI is a more accurate indicator of changes in costs for colleges and universities than the more familiar Consumer Price Index. In 2005, Commonfund Institute assumed responsibility for maintaining HEPI and calculating its annual rate of change.