FRED has added 204 monthly series on corporate bond yield curves based on methodology developed by the U.S. Treasury. These high-quality market (HQM) yields are used to discount future pension liabilities as required by the Pension Protection Act. The HQM yield curve uses data from a set of corporate bonds rated AAA, AA, or A that accurately represent the high-quality corporate bond market. Yields are projected for corporate bonds beyond 30 years maturity.