Year % of total fuel combustion 1960 0.8547008547008548 1961 0.8695652173913043 1962 0.8064516129032258 1963 0.7874015748031495 1964 0.7751937984496123 1965 1.4285714285714286 1966 2 1967 1.4084507042253522 1968 2.013422818791946 1969 2.2556390977443606 1970 2.2727272727272725 1971 51.33587786259542 1972 51.37135393992164 1973 45.84681769147788 1974 46.85522887979159 1975 42.66294876263506 1976 44.98587570621469 1977 45.27284263959391 1978 44.26330359889264 1979 45.13023782559456 1980 49.18787222523011 1981 48.85624849506381 1982 49.04306220095694 1983 48.93162393162393 1984 55.34114403859408 1985 57.36344779903204 1986 57.730836236933804 1987 58.31218274111675 1988 59.89197839567915 1989 59.16270218839201 1990 65.3659075834623 1991 64.68023255813954 1992 66.92316660837122 1993 67.0109283055122 1994 65.9400544959128 1995 65.61391057487579 1996 64.70521670250085 1997 65.0656455142232 1998 64.91525423728814 1999 66.23417064563007 2000 63.57128247085294 2001 62.74318115162771 2002 62.38634254963815 2003 65.46453718014769 2004 62.997579904865226 2005 63.402655206814515 2006 62.52022796031802 2007 61.110027945668406 2008 60.252889711986725 2009 61.74106267564212 2010 64.32442196531792 2011 66.91484411354119 2012 65.0639955481358 2013 64.56920036322846 2014 63.243549466961944