The U.S. Treasury yield curve derived using on-the-run treasuries. The on-the-run Treasury curve is the primary benchmark used in pricing-fixed income securities. 

|||While the on-the-run Treasury yield curve is typically used to price fixed-income securities, its shape is sometimes distorted by up to several basis points if an on-the-run Treasury goes "on special". A Treasury goes on special when its price is temporarily bid up, usually as the result of demand by securities dealers to use the security as a hedging vehicle.