Year % of energy use 1960 -13.507026696637741 1961 -11.579360701573279 1962 -8.951253644036317 1963 -10.931869236295794 1964 -13.270191288365535 1965 -11.229933440722693 1966 -11.071026511621607 1967 -9.078232179045237 1968 -9.465761836143706 1969 -8.905063409499475 1970 -8.243641009633969 1971 -30.64660201684039 1972 -31.75090225958682 1973 -30.34263656189771 1974 -27.080890488357102 1975 -22.74822191900366 1976 -23.09458892040317 1977 -19.913086613380997 1978 -17.903679041856137 1979 -19.19401346039672 1980 -12.968427916271665 1981 -9.272514608141615 1982 -8.250448150037437 1983 -10.655093765361906 1984 -13.058400493151515 1985 -12.235016917350988 1986 -12.385561603801682 1987 -11.043155515457933 1988 -10.850937841954158 1989 -14.548186647311297 1990 -21.025363045019112 1991 -19.23691957388988 1992 -21.72132638491305 1993 -20.867383569531896 1994 -23.56195042457921 1995 -23.19087936597538 1996 -22.897439797272227 1997 -23.540586017080575 1998 -24.973530369049467 1999 -23.926491463790672 2000 -26.237634944662464 2001 -26.692106025626 2002 -25.859262926284583 2003 -26.32099752833947 2004 -25.363801400738613 2005 -24.89260015010321 2006 -22.80924336335557 2007 -21.081200005800326 2008 -21.03742550550093 2009 -18.812719483396904 2010 -17.78401777114564 2011 -16.687857748317384 2012 -14.782849522004762 2013 -14.636310244531051 2014 -13.745040775634937 2015 42.152562658038576