1980-1999

United States #1934 1981 18¢ Coming Through the Rye Mint Single

United States #1919 18¢ Comprehending the Universe Mint Single

United States #1914 18¢ Cooling Electric Systems Mint Single

United States #1926 18¢ Edna St. Vincent Millay Mint Single

United States #1935 18¢ James Hoban Mint Single

United States #1918 18¢ Landing Mint Single

United States #1931 18¢ National Farmers Bank Mint Single

United States #1928 18¢ New York Univ. Library Mint Single

United States #1930 18¢ Palace of Arts Mint Single

United States #1916 18¢ Probing the Planets Mint Single

United States #1920 18¢ Professional Management Mint Single

United States #1913 18¢ Releasing Boosters Mint Single