CAHA suggested that a Canadian withdrawal was possible. In 1986, the IOC voted to allow all athletes to compete in Olympic Games starting in 1988, but let the individual sport federations decide if they wanted to allow professionals. After the 1972 retirement of IOC President Brundage, the Olympic amateurism rules were steadily relaxed, amounting only to technicalities and lip service, until being completely abandoned in the 1990s (in the United States, the Amateur Sports Act of 1978 prohibits national governing bodies from having more stringent standards of amateur status than required by international governing bodies of respective sports. The act caused the breakup of the Amateur Athletic Union as a wholesale sports governing body at the Olympic level). Olympic regulations regarding amateur status of athletes were eventually abandoned in the 1990s with the exception of wrestling, where the amateur fight rules are used due to the fact that professional wrestling is largely staged with pre-determined outcomes. Starting from the 2016 Summer Olympics, professionals were allowed to compete in boxing, though amateur fight rules are still used for the tournament. Contribution of amateurs Many amateurs make valuable contributions in the field of computer programming through the open source movement. Amateur dramatics is the performance of plays or musical theater, often to high standards, but lacking the budgets of professional West End or Broadway performances. Astronomy, chemistry, history, linguistics, and the natural sciences are among the fields that have benefited from the activities of amateurs. Gregor Mendel was an amateur scientist who never held a position in his field of study. Radio astronomy was founded by Grote Reber, an amateur radio operator. Radio itself was greatly advanced by Guglielmo Marconi, a young Italian man who started out by tinkering with a coherer and a spark coil as an amateur electrician. Pierre de Fermat was a highly influential mathematician whose primary vocation was law. In the 2000s and 2010s, the distinction between amateur and professional has become increasingly blurred, especially in areas such as computer programming, music and astronomy. The term amateur professionalism, or pro-am, is used to describe these activities. List of amateur pursuits Amateur astronomy, including a list of notable amateur astronomers Amateur chemistry, including a list of notable amateur chemists Amateur film Amateur geology or rockhounding, including a list of notable amateur geologists Amateur journalism Amateur radio Amateur sports Amateur theatre Amateur pornography Arts and crafts or handicraft, including a