Year	% of total energy use
1960	27.872272025186422
1961	30.243309235409587
1962	30.78264333372564
1963	30.289980751164457
1964	31.832583385072297
1965	30.408899370262052
1966	31.23877892193361
1967	33.75934197762264
1968	34.48371372994412
1969	42.95602262176077
1970	45.65385237753994
1971	4.255306748844664
1972	4.275891417308727
1973	4.170883010253508
1974	4.1294956684332025
1975	4.497427655353982
1976	4.62288433964726
1977	4.917217341237013
1978	4.842175827802192
1979	5.083598991145428
1980	5.2271422897681195
1981	5.591663659733165
1982	5.610926197446573
1983	5.921232307753459
1984	5.5954219559612515
1985	5.530361245580797
1986	5.357115531178767
1987	5.520308240573671
1988	5.403539413815089
1989	5.3752779895009475
1990	1.9973277309893032
1991	2.257503006603811
1992	2.335211073994763
1993	2.369627222604366
1994	2.325168271023543
1995	2.5029605884709794
1996	2.345977106908549
1997	2.3370495470712687
1998	2.427502422201619
1999	2.520614965153835
2000	2.7094330361195564
2001	2.6524979300297247
2002	2.633507195966057
2003	2.463698059393787
2004	2.4593825656201913
2005	2.6160162677728125
2006	2.5045681554662105
2007	2.5726621142698556
2008	2.9577216227963286
2009	3.0628424567724126
2010	2.8362981516762087
2011	2.7370635006906823
2012	2.7240742531039643
2013	2.658602725603481
2014	2.5740956889244444
2015	19.7000041519165