Year	% of total fuel combustion
1960	23.94284038106413
1961	24.266413481451092
1962	24.329961612466597
1963	24.20430589546633
1964	24.26020311410508
1965	23.678389675473706
1966	23.54795326552912
1967	23.737202830403096
1968	24.226780770799007
1969	24.47216029485861
1970	24.584595289961474
1971	25.297521303994603
1972	25.47954684102997
1973	25.75518890086505
1974	26.010458445448545
1975	27.426880811496197
1976	27.087021326758546
1977	26.934558555359796
1978	27.980221101486705
1979	27.418591143222464
1980	27.313986167307807
1981	27.637059848454154
1982	28.445236815207853
1983	28.94000222562724
1984	28.561444499098215
1985	28.66085510630754
1986	29.383254748504555
1987	29.386885030752193
1988	29.38719879117834
1989	29.213695422014887
1990	29.711200945237145
1991	29.363768913608144
1992	29.560789306174403
1993	29.416754879289787
1994	30.029550589363986
1995	30.326923320699226
1996	30.17004532199698
1997	29.73286717571805
1998	30.3013095847501
1999	30.9647852783485
2000	30.324364609396945
2001	30.548626593365967
2002	31.268883673266995
2003	31.24630707852677
2004	31.322730206038404
2005	31.556029403512703
2006	32.10317706479828
2007	31.642716393521415
2008	30.952668028745702
2009	31.680967917153335
2010	31.372916276456262
2011	31.685897290891976
2012	33.42887158904183
2013	32.94839408155901
2014	33.24265705346876