Year	% of total fuel combustion
1960	34.85616098632466
1961	36.19068092653302
1962	37.004320858596415
1963	37.98970643009515
1964	38.86150394343214
1965	39.04687422001098
1966	40.27317809770579
1967	39.7103209019948
1968	38.31415638713244
1969	39.616810877626705
1970	40.89353734908645
1971	43.06602254428341
1972	42.60255771466534
1973	43.51432761910769
1974	43.004789513486266
1975	43.06327267676066
1976	43.58300256026942
1977	43.527109551604305
1978	44.568160281575736
1979	44.7922184234603
1980	46.024400504838034
1981	45.12131324975196
1982	44.28700744490218
1983	44.30624343388864
1984	43.1846368498566
1985	43.56506698071544
1986	44.03025198035772
1987	44.31486880466473
1988	43.34248333392749
1989	43.95497981034515
1990	44.972704533420966
1991	43.96271561729939
1992	44.88409053543049
1993	42.29783223374175
1994	41.780887385062414
1995	42.051471733374875
1996	41.839679208514475
1997	41.21968853195772
1998	41.9267800295054
1999	41.9593381721689
2000	43.283123860692704
2001	43.778242521567016
2002	44.22174347926445
2003	45.34438056588885
2004	44.92171366350017
2005	45.77426339075591
2006	46.6734268491916
2007	46.4563153351875
2008	45.626156450533436
2009	44.38735522076113
2010	43.805708772886476
2011	44.96442255062944
2012	45.84523500389509
2013	44.0521190020901
2014	41.930659081992935