Year	% of total fuel combustion
1971	22.523164647184608
1972	22.26537216828479
1973	22.646153846153844
1974	22.215149586250796
1975	20.794701986754966
1976	20.582877959927142
1977	20.706791827719492
1978	21.549999999999997
1979	21.280749707145645
1980	17.858494135452137
1981	14.45648113559955
1982	9.105905641702408
1983	9.256402344955262
1984	9.860859044162128
1985	8.410451823625477
1986	10.50012440905698
1987	16.295781177561427
1988	18.895682078716085
1989	18.98422090729783
1990	0
1991	0
1992	0
1993	0
1994	0
1995	0
1996	0
1997	0
1998	0
1999	0
2000	0
2001	0
2002	0
2003	0
2004	0
2005	0
2006	0
2007	0
2008	0
2009	0
2010	0
2011	0
2012	0
2013	0
2014	0