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Treasury Bonds, and why has the NYSE 20+ Year Treasury Bond index (AXTWEN) gone up so much in the last year (2011)?
The NYSE 20 Year Plus Treasury Bond Index (AXTWEN) is a multiple-security fixed income index that aims to track the total returns of the long-term 20 year and greater maturity range of the U.S. Treasury bond market. The index constituent bonds are weighted by their relative amounts outstanding.One cannot directly invest in an Index. Index Bond Maturities 24 to 27 Years  20.36% /27 to 29 Years     79.64% Index Duration 17.47 Years An oversimplification of how bonds value changes as rates change is they are inversely related based on the duration of the bond.  Think of duration as the time-weighted average of all the coupons and the final payment. In this case, a drop in rates of about 1% will cause a rise in value of about 17.4%. Long term rates took a drop in the last year.