Year	% of energy use
1971	-45.64426701550332
1972	-54.48266794988
1973	-60.847683199385585
1974	-67.31916369935047
1975	-51.123041831316414
1976	-58.92886556989986
1977	-58.80774094853048
1978	-50.949382846650536
1979	-64.25630730755313
1980	-57.15400710310093
1981	-39.92276592825306
1982	-35.27013962527743
1983	-36.131913155166835
1984	-42.701974940358625
1985	-47.533956591945156
1986	-45.998026526532264
1987	-41.70996309132011
1988	-44.65569038189309
1989	-50.88159037353211
1990	-52.63681146823222
1991	-51.91316469427429
1992	-55.30082606249239
1993	-54.22040823160399
1994	-56.053775182837676
1995	-55.66760795267321
1996	-57.661439530738605
1997	-61.60478839226249
1998	-60.70871019874642
1999	-57.085784663467095
2000	-61.15644023903235
2001	-59.05236006322011
2002	-55.417231846751356
2003	-58.41938136357472
2004	-58.44694295495843
2005	-60.94579224929308
2006	-62.20092897835471
2007	-61.368350788368595
2008	-57.50114513318716
2009	-55.215997987340856
2010	-58.1846469770254
2011	-54.57736214103884
2012	-51.570981045586905
2013	-48.12737029537663
2014	-48.80313559733925