Year	% of total fuel combustion
1971	37.05406771096513
1972	37.55266088809259
1973	38.03394313422966
1974	40.81275104691907
1975	42.23139184256467
1976	42.68792206354478
1977	42.41151331409578
1978	36.55239579275419
1979	39.008099497140236
1980	39.88433038134828
1981	41.329450059962305
1982	44.14845957681438
1983	46.2050036947113
1984	47.710105478053755
1985	47.909263011059814
1986	48.79946344735078
1987	50.760270738233906
1988	48.5757074662257
1989	49.71396936704189
1990	50.767364270548995
1991	51.588552719335475
1992	52.31557807020174
1993	54.95924317248767
1994	55.90516088777967
1995	55.60605630201973
1996	55.47907938407966
1997	55.22879177377892
1998	56.304896516910645
1999	55.70304818092428
2000	56.6018707611628
2001	59.282427868815304
2002	58.422703248020724
2003	57.92503598022652
2004	58.277704911614435
2005	56.81150395983731
2006	56.583829326737266
2007	57.11841395599693
2008	58.00214265966271
2009	53.64735607291102
2010	57.25273590749536
2011	55.78606939498716
2012	54.932480337680744
2013	53.879405896696966
2014	54.768659806462495