Year	% of total energy
1960	54.994828279902826
1961	54.838206026885075
1962	50.13486057208687
1963	46.89303911469657
1964	44.91927730462725
1965	42.5090200559124
1966	39.177557455789305
1967	38.02604564636631
1968	36.11291959246811
1969	34.08936710412753
1970	32.79012777077308
1971	44.02604291485134
1972	43.02538340379919
1973	41.70917760196144
1974	41.04511425038146
1975	39.39838022482184
1976	38.3539243391454
1977	36.73649971548142
1978	35.3058753835016
1979	34.729743438316625
1980	34.46644053875656
1981	34.33261746744467
1982	33.56879561086176
1983	33.330331854812854
1984	32.482517739356844
1985	31.881371858066895
1986	31.21538329748232
1987	30.407544594404776
1988	29.598316814570666
1989	29.247718980103855
1990	16.961617312194644
1991	17.09558730797793
1992	17.55354952275793
1993	17.549777107979054
1994	17.79990151994836
1995	17.39434856238326
1996	17.238206227276386
1997	17.184610382371805
1998	17.247060675985022
1999	17.036450411431385
2000	16.62218138497011
2001	16.142897993601018
2002	15.779686007714655
2003	14.85535596689955
2004	13.886864376200354
2005	13.217112204214828
2006	12.682579310472855
2007	12.052148914995408
2008	11.625442468778179
2009	11.348643271077808
2010	10.67407463594167
2011	10.171475221465105
2012	9.912577846661998
2013	9.744982690494837
2014	9.499573966039915
2015	3.1460913773944923