evidence: Bougainville [edit]A secessionist revolt in 1975–76 on Bougainville Island resulted in an eleventh-hour modification of the draft Constitution of Papua New Guinea to allow for Bougainville and the other eighteen districts to have quasi-federal status as provinces. A renewed uprising on Bougainville started in 1988 and claimed 20,000 lives until it was resolved in 1997. Bougainville had been the primary mining region of the country, generating 40% of the national budget. The native peoples felt they were bearing the adverse environmental effects of the mining, which contaminated the land, water and air, without gaining a fair share of the profits.[45] The government and rebels negotiated a peace agreement that established the Bougainville Autonomous District and Province. The autonomous Bougainville elected Joseph Kabui as president in 2005, who served until he died in 2008. He was succeeded by his deputy John Tabinaman as acting president while an election to fill the unexpired term was organised. James Tanis won that election in December 2008 and served until the inauguration of John Momis, the winner of the 2010 elections. As part of the current peace settlement, a non-binding independence referendum was held, between 23 November and 7 December 2019. The referendum question was a choice between greater autonomy within Papua New Guinea and full independence for Bougainville, and voters voted overwhelmingly (98.31%) for independence.[46] Negotiations between the Bougainville government and national Papua New Guinea on a path to Bougainville independence began after the referendum, and are ongoing.