[Code of Federal Regulations] [Title 31, Volume 2] [Revised as of July 1, 2005] From the U.S. Government Printing Office via GPO Access [CITE: 31CFR359.8] [Page 451] TITLE 31--MONEY AND FINANCE: TREASURY CHAPTER II--FISCAL SERVICE, DEPARTMENT OF THE TREASURY PART 359_OFFERING OF UNITED STATES SAVINGS BONDS, SERIES I--Table of Contents Subpart A_General Information Sec. 359.8 How does interest accrue on Series I savings bonds? A bond accrues interest based on both a fixed rate of return and a semiannual inflation rate. A single, annual rate called the composite rate reflects the combined effects of the fixed rate and the semiannual inflation rate. For more information, see Appendix B of part 359.