Consumer prices, inflation-linked bonds indexing

The first step for estimating future streams is to know the expected inflation. To do this, the procedure needs the future trend of index in which the inflation expectation is built. The inflation expectation determined by countries is based on a different basket of products and services. For instance, inflation-linked bonds issued in the United Kingdom or UK index-linked gilts, are linked to the Retail Price Index (RPI) inflation-linked bonds issued in the United States or TIPS are linked to the Consumer Price Index (CPI). Table 6.1 summarizes the key global inflation indices used by the major issuers of inflation-linked bonds. 

There have been many different structures of inflation-linked bonds issued over time, but the most widely used form is one where principal and income are adjusted for changes in the relevant consumer price index between issue date and cash flow payment date, subject to an indexation... 

An index-linked bond has its coupon or maturity value or sometimes both linked to a specific index. When governments issue index-linked bonds, the cash flows are linked to a price index such as consumer or commodity prices. Corporations have also issued index-linked bonds that are connected to either an inflation index or a stock market index. For example, Kredit Fuer Wiederaufbau, a special purpose bank in Denmark, issued a floating-rate note in March 2003 whose coupon rate will be linked to the Eurozone CPI (excluding tobacco) beginning in September 2004. Inflation-indexed bonds are detailed in Chapter 8. 

Index-linked gilts, like all other linkers covered in this chapter, are known as capital indexed bonds, where the income and principal are adjusted for changes in a consumer price index, subject to a lag. In the United Kingdom, the index is the RPI and the lag is eight months. The market trades on a clean price basis, with the quoted price a cash price (not a real price), including inflation accretion. 

Duration increases as coupon and yield decrease. The lower the coupon, the greater the relative weight of the cash flows received on the maturity date, and this causes duration to rise. T ong the non—plain vanilla types of bonds are some whose coupon rate varies according to an index, usually the consumer price index. Index-linked bonds generally have much lower coupons than vanilla bonds with similar maturities. This is true because they are inflation-protected, causing the real yield required to be lower than the nominal yield, but their durations tend to be higher. 

Certain countries have markets in bonds whose coupon or final redemption payment, or both, are linked to their consumer price indexes. Generally, the most liquid markets in these inflation-indexed, or index-linked, debt instruments are the ones for government issues. Investors experiences with the bonds differ, since the securities were introduced at different times in different markets and so are designed differently. In some markets, for instance, only the coupon payment, and not the redemption value, is index-linked. This makes comparisons in terms of factors such as yield difficult and has in the past hindered arbitrageurs seeking to exploit real yield differences. This chapter highlights the basic concepts behind indexed bonds and how their structures may differ from market to market. 

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