Year	% of total fuel combustion
1971	35.23316062176166
1972	39.10112359550561
1973	25.510204081632654
1974	26.034063260340634
1975	21.889400921658986
1976	20.94017094017094
1977	21.16935483870968
1978	23.665480427046266
1979	26.119402985074625
1980	39.353891336270195
1981	37.264957264957275
1982	35.51554828150573
1983	38.288288288288285
1984	36.28808864265928
1985	36.31123919308357
1986	35.775862068965516
1987	37.70718232044199
1988	34.30962343096235
1989	45.46783625730994
1990	37.742504409171076
1991	37.00787401574803
1992	35.51401869158878
1993	27.272727272727277
1994	22.66009852216749
1995	26.486486486486484
1996	24.731182795698924
1997	16.783216783216783
1998	22.72727272727273
1999	16.78082191780822
2000	15.259740259740258
2001	16.77018633540373
2002	11.466666666666667
2003	13.089005235602095
2004	13.715710723192021
2005	11.780104712041886
2006	17.941952506596305
2007	16.931216931216934
2008	13.477088948787062
2009	20.689655172413794
2010	26.463104325699742
2011	26.811594202898554
2012	18.39080459770115
2013	15.934065934065933
2014	22.0873786407767