Year	% of energy use
1971	18.462311368508423
1972	-0.7326551997675671
1973	-0.37331752567537146
1974	16.377352737465873
1975	6.699465457569725
1976	-28.716842845169143
1977	-39.642442112401525
1978	-43.48719419007258
1979	-53.697253833305766
1980	-48.45793521494168
1981	-29.785814871647066
1982	-49.31028492251739
1983	-77.53011338078989
1984	-113.00925439595788
1985	-117.62227739698274
1986	-129.1831479172355
1987	-131.75443383572411
1988	-135.7551807294488
1989	-130.93681829338414
1990	-121.52917032274127
1991	-95.26798178540929
1992	-81.75305955887404
1993	-74.46819971598957
1994	-80.69363551098138
1995	-85.28967258925627
1996	-83.24364766060278
1997	-66.53206407277835
1998	-77.49811150777188
1999	-71.67339220638561
2000	-58.61331379090664
2001	-54.012370034827185
2002	-55.08936972482918
2003	-50.69567535992287
2004	-52.0792254693467
2005	-45.39604063428865
2006	-40.71882506428807
2007	-28.354140734132322
2008	-26.966162357463485
2009	-24.720789395292478
2010	-21.70277535937533
2011	-14.73706169259816
2012	-11.868809790613026
2013	-5.760513036768271
2014	-5.505028940595212