Year	% of energy use
1960	16.741830222416546
1961	17.66510538340047
1962	19.02912863184424
1963	21.15892715181429
1964	21.97776468695985
1965	23.720467957653884
1966	24.552189197950888
1967	24.737427882793845
1968	26.723569716729273
1969	29.386582329523993
1970	29.536548491990192
1971	15.646038350153857
1972	15.389909996925887
1973	16.359268941561915
1974	15.097432143217986
1975	15.190058377619087
1976	16.877678901210402
1977	16.052828945035486
1978	18.075448886118203
1979	14.764810741136863
1980	12.160965416175566
1981	10.679687427854086
1982	13.140147399660199
1983	15.324389537689317
1984	14.314677800876025
1985	15.811768708471469
1986	13.851660083978544
1987	15.513012123495361
1988	15.928353738928749
1989	16.575228542750345
1990	15.218567153909092
1991	14.125164628982342
1992	13.034903542281691
1993	13.732533687826441
1994	13.069616355948035
1995	13.310526398968502
1996	13.98548530045789
1997	14.048663778975607
1998	13.94323577164715
1999	16.516267415703833
2000	16.35155133561933
2001	15.849438664713999
2002	17.69237938388689
2003	17.41731953246847
2004	17.53830201489077
2005	17.23323049760421
2006	16.911829320147984
2007	17.743780668313907
2008	15.561918117302854
2009	14.53594399212062
2010	15.102415937632552
2011	11.821435598407744
2012	9.797236566366912
2013	8.134615937249054
2014	5.093367608691325
2015	20.518379034740377