<Tr> <Th> Years of service </Th> <Td> 1961--1985 </Td> </Tr> <Tr> <Th> Rank </Th> <Td> Major general </Td> </Tr> <P> Muhammadu Buhari GCFR is the President of Nigeria, in office since 2015 . He is a retired major general in the Nigerian Army and previously served as the nation's head of state from 31 December 1983 to 27 August 1985, after taking power in a military coup d'état . The term Buharism is ascribed to the Buhari military government . </P> <P> He unsuccessfully ran for the office of president of Nigeria in the 2003, 2007 and 2011 general elections . In December 2014, he emerged as the presidential candidate of the All Progressives Congress for the March 2015 general elections . Buhari won the election, defeating the incumbent President Goodluck Jonathan . This marked the first time in the history of Nigeria that an incumbent president lost to an opposition candidate in a general election . He was sworn in on 29 May 2015 . </P>

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