Year	% of total fuel combustion
1960	35.77098145431291
1961	34.76882719422888
1962	33.1805621082429
1963	32.726112617642364
1964	32.93620871663399
1965	35.01639543356813
1966	35.70835511547096
1967	34.80579270957779
1968	35.89549306841781
1969	36.641100238032266
1970	36.13298981720034
1971	31.882516953758184
1972	29.067487460100317
1973	26.04652143655497
1974	27.951004667265593
1975	25.936871970682112
1976	24.242293318355618
1977	24.69355917093827
1978	23.6947877025698
1979	24.40345699831366
1980	24.203401749219882
1981	22.460260914428915
1982	21.02493003671468
1983	21.411374458295438
1984	22.211461302194305
1985	22.829115723628092
1986	22.036131525781048
1987	22.465974212034382
1988	21.96731144099565
1989	21.010425020048114
1990	20.743849493487698
1991	19.633161349577247
1992	20.080734966592427
1993	19.822780353265653
1994	20.233022438094107
1995	20.28584735401991
1996	20.199771848306945
1997	20.201185455374443
1998	18.166926258123425
1999	17.989576796092667
2000	17.34192840488273
2001	18.02325581395349
2002	17.880794701986755
2003	17.362488116256962
2004	16.45209377964494
2005	14.818314345877651
2006	15.05278031751309
2007	14.90959587371762
2008	14.581543220484619
2009	12.762064725113223
2010	13.455657492354739
2011	14.681913351586406
2012	14.626243182547322
2013	15.804244316211017
2014	15.695883506020724