Source: Board of Governors of the Federal Reserve System (US)  

Release: H.15 Selected Interest Rates  

Units:  Percent, Not Seasonally Adjusted

Frequency:  Daily

For further information regarding treasury constant maturity data, please refer to the H.15 Statistical Release notes and Treasury Yield Curve Methodology.

For questions on the data, please contact the data source. For questions on FRED functionality, please contact us here.

Source: Board of Governors of the Federal Reserve System (US)  

Release: An Arbitrage-Free Three-Factor Term Structure Model and the Recent Behavior of Long-Term Yields and Distant-Horizon Forward Rates  

Units:  Percent, Not Seasonally Adjusted

Frequency:  Daily

Kim and Wright (2005) produced this data by fitting a simple three-factor arbitrage-free term structure model to U.S. Treasury yields since 1990, in order to evaluate the behavior of long-term yields, distant-horizon forward rates, and term premiums. For the full paper, please go to http://www.federalreserve.gov/pubs/feds/2005/200533/200533abs.html

Source: Federal Reserve Bank of St. Louis  

Release: Interest Rate Spreads

Units:  Percent, Not Seasonally Adjusted

Frequency:  Daily

This series is a measure of expected inflation (on average) over the five-year period that begins five years from today.

This series is constructed as:
(((((1+((BC_10YEAR-TC_10YEAR)/100))^10)/((1+((BC_5YEAR-TC_5YEAR)/100))^5))^0.2)-1)*100

where BC10_YEAR, TC_10YEAR, BC_5YEAR, and TC_5YEAR are the 10 year and 5 year nominal and inflation adjusted Treasury securities.
Starting with the update on June 21, 2019, the Treasury bond data used in calculating interest rate spreads is obtained directly from the U.S. Treasury Department.