Year	% of total fuel combustion
1960	12.914732270493257
1961	13.27829286628068
1962	13.154509592531792
1963	13.139500126462947
1964	13.111992730335334
1965	13.042242998521573
1966	13.50660683121416
1967	13.520548985844878
1968	13.478407637558302
1969	12.98578991607733
1970	12.395593344990356
1971	12.064357962755508
1972	12.264986003159065
1973	12.350746379238299
1974	12.177814347790832
1975	13.018672358696287
1976	12.776972220228268
1977	13.24939512000992
1978	13.426315979723997
1979	13.388553449334918
1980	13.613579122673166
1981	13.972720376704975
1982	14.34884218736713
1983	14.655678241852032
1984	14.866804632116596
1985	14.840553751137655
1986	15.401712358384502
1987	15.817168681556359
1988	16.817164157738926
1989	17.49685534591195
1990	18.4674071580837
1991	18.899572307880177
1992	20.09823259623753
1993	20.59290159756934
1994	20.878197174078377
1995	20.840722316700163
1996	20.893173380715083
1997	21.678525498491606
1998	22.627332431153537
1999	23.58232399464958
2000	23.517612869046495
2001	23.538102760851576
2002	23.823649106940987
2003	23.60202168945418
2004	24.160266955203486
2005	24.298935787181048
2006	24.591783180700443
2007	25.164627004804363
2008	25.22204436313744
2009	26.295908211497217
2010	25.354156434772076
2011	25.930885357773413
2012	25.40363405645477
2013	25.751672780352468
2014	27.417473611540064