The semi-postal stamp is also known as a charity stamp. They are issued to raise money for a charitable cause or purpose. Usually the money raised is used for early childhood education, recovery from natural disasters, health care and research and war funding or recovery efforts. The stamps usually show two values separated by a plus sign, sometimes only the plus sign is found on the stamp. Buyers pay an extra fee over face value for semi-postal stamps (example: a face value stamp sells for 10 cents, an extra 5 cents goes to charity, for a total of 15 cents). This type of stamp became popular in Europe beginning in the early 20th century and they continue to be issued today. The United States issued its first semi-postal stamp, the Breast Cancer Research stamp, in 1998.