The 91 day treasury bill controls the federal student loan rate. Auctions for the 91 day treasury bill occur every Monday. The price of the 91-day Treasury Bill at that auction is the base rate for student loans, using the investment yield (as opposed to the discount yield). http://www.bankrate.com/rates/interest-rates/91-day-treasury-bill.aspx gives the current rate of the 91 day treasury bill.
. You can also visit the United States treasury website for more detailed information at http://www.treasurydirect.gov/RI/OFBills
