Definition. 1  A blood clot is a thickened mass in the blood formed by tiny substances called platelets. Clots form to stop bleeding, such as at the site of cut. 2  As soon as a blood vessel wall is damagedâby a cut or similar traumaâa series of reactions normally takes place to activate platelets to stop the bleeding.
Series EE bonds mature after 30 years, meaning they can earn interest for that period of time. EE bonds are sold for half of face value and the U.S. Treasury Department guarantees they will reach face value after 20 years. Bonds must be owned for at least one year before redemption.
If you have three bonds with maturities of 12, 14 and 20 years and their values make up 25, 35 and 40 percent of the portfolio respectively, the average maturity of the bond portfolio is 12 x 25 percent + 14 x 35 percent + 20 x 40 percent, or 15.9 years. The same formula applies to effective duration. So if the effective durations were six, nine and 11, the effective duration of the portfolio equals 6 x 25 percent +9 x 35 percent +11 times 40 percent, or 9.05. In simpler terms, on average, the bonds in the portfolio will mature in 15.9 years. If the yields were to increase by 1 percent on each on these three bonds, the portfolio's value would decline by 9.05 percent. 1  BondView:Duration.  BondEdge: Effective Duration -- Subtleties and Considerations.