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.
Updated January 27, 2016. Have you ever wondered why different Series EE savings bonds mature at different dates? For example, the EE bonds issued in 1981 and 1982 took only eight years to reach full face value, yet the same EE bonds issued in 2003 took twenty years to reach face value.