Quantized Hall conductance was discovered in 1980, related to the electron charge. Laughlin proposed a fluid of fractional charges in 1983, to explain the fractional quantum Hall effect (FQHE) seen in 1982, for which he shared the 1998 Physics Nobel Prize. In 1997, experiments directly observed an electric current of one-third charge. The one-fifth charge was seen in 1999 and various odd fractions have since been detected.