Not a series but a combined collection of stamps honoring statehood anniversaries.
Letter Rate 25¢ Package Rate 25¢ Postcard Rate 15¢ Effective 4/3/1988 United States 1/13/1990 First Elected Black Governor in the US The first black person to be elected governor of an American state, Douglas Wilder, took office in Virginia. American President George H W Bush (1/20/1989-1/20/1993) British Prime Minister Margaret Thatcher (5/4/1979-11/28/1990) German President Richard von Weizsäcker (7/1/1984-6/30/1994)