treasury inflation-protected security means: These Treasury bonds were first issued in 1997 by the U.S. Treasury. They are designed to help investors protect themselves against inflation fluctuations by linking. The principal is adjusted to the consumer price index. The inflation rate for the preceding year is used to adjust the principal each year. For measuring inflation rates, the index is the U.S. City Average All Items Consumer Price Index (CPI-U), published by the Bureau of Labor Statistics BLS monthly. These bonds They are taxable. In fact, both interest and principal growth are subject to tax. The U.S. Treasury sells TIPS as one type of inflation-indexed securities; Series I Savings Bonds is the other. (in Stock Market Dictionary)