Year	% of total fuel combustion
1971	34.368070953436806
1972	34.168564920273354
1973	37.7906976744186
1974	39.05472636815921
1975	35.11450381679389
1976	34.84486873508353
1977	36.38392857142856
1978	35.991379310344826
1979	38.235294117647065
1980	37.67258382642998
1981	37.5249500998004
1982	37.864077669902905
1983	36.94779116465863
1984	36.86131386861314
1985	33.1588132635253
1986	34.65346534653466
1987	27.494456762749447
1988	29.439252336448597
1989	29.904306220095695
1990	34.271099744245525
1991	32.637075718015666
1992	25.4278728606357
1993	34.193548387096776
1994	33.39449541284404
1995	40.47619047619048
1996	41.12676056338028
1997	34.090909090909086
1998	38.01546391752578
1999	34.84320557491289
2000	37.82327586206897
2001	34.390243902439025
2002	42.62899262899263
2003	37.8167641325536
2004	42.699999999999996
2005	44.46546830652791
2006	40.63136456211813
2007	43.72549019607843
2008	26.912928759894463
2009	30.440967283072546
2010	29.113924050632907
2011	29.1358024691358
2012	26.486013986013983
2013	29.03946388682055
2014	36.605316973415135