Year	% of total fuel combustion
1990	19.00031046258926
1991	18.028004667444574
1992	15.764828303850157
1993	12.882238126219908
1994	14.067914067914067
1995	12.956068503350707
1996	10.999281092739038
1997	11.43911439114391
1998	10.636808957312807
1999	9.915966386554622
2000	10.567514677103718
2001	9.567617295308189
2002	10.155535224153708
2003	10.338517840805123
2004	10.46712802768166
2005	10.839445802770987
2006	12.096774193548386
2007	11.652035115722267
2008	10.513643659711075
2009	9.21985815602837
2010	9.351927809680065
2011	10.484581497797357
2012	11.355633802816904
2013	11.742777260018638
2014	11.154219204655673