The 2011–12 National Postsecondary Student Aid Study restricted-use data file contains data on a sample of 95,000 undergraduate and 16,000 graduate students attending 1,500 postsecondary institutions in the 50 states and the District of Columbia that were eligible to participate in the federal financial aid programs in Title IV of the Higher Education Act (prior cycles of NPSAS also included institutions from Puerto Rico). NPSAS focuses on how students and their families pay for postsecondary education, and contains a wide range of demographic information about the nation's postsecondary students.