Year	% of total energy use
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0.0023620050071759633
1982	0.002178876652272568
1983	0.0011678356339242671
1984	0.0022617014780219155
1985	3.0503287875604643
1986	3.267642631220501
1987	3.1307699015015658
1988	3.00466776332553
1989	3.034613919343037
1990	3.1252024526222355
1991	3.2991806431507946
1992	3.0262389404692343
1993	3.0350400186999225
1994	2.9863287795019415
1995	2.990657446542986
1996	3.0517307308523995
1997	3.049216561056936
1998	3.1237455437753363
1999	3.2251675315053934
2000	3.2805549306715065
2001	3.275442854469801
2002	3.5046215905432034
2003	3.5116415943590282
2004	3.7834884163535567
2005	3.9417496014581137
2006	3.626977281350223
2007	3.599088174744898
2008	4.660120710083078
2009	4.8686937154805445
2010	4.884731162397658
2011	4.847524600046701
2012	4.697738939812078
2013	4.963834766706839
2014	5.191551468281525
2015	5.245322035134604