Year % of total fuel combustion 1985 48.302207130730054 1986 46.71875 1987 47.71386430678466 1988 48.160999306037475 1989 48.02631578947369 1990 51.555209953343706 1991 56.16065350578625 1992 62.558502340093604 1993 61.064189189189186 1994 64.5631067961165 1995 64.39024390243902 1996 67.70472895040369 1997 64.89988221436984 1998 73.47417840375587 1999 71.56177156177156 2000 73.38530066815144 2001 71.65178571428571 2002 73.11715481171548 2003 70.11866235167207 2004 69.95798319327731 2005 69.72727272727272 2006 61.3452188006483 2007 62.22910216718266 2008 61.89735614307932 2009 61.40221402214022 2010 63.03886925795052 2011 59.91019884541373 2012 58.75509016870273 2013 59.75348338692389 2014 63.8215859030837