Year	% of total electricity output
1990	37.694270850374636
1991	40.27640671273447
1992	41.51295233899168
1993	41.613996448153095
1994	41.64447645746383
1995	39.789509519655375
1996	39.50584160362056
1997	39.814373480468184
1998	40.149836430108074
1999	41.10664460094136
2000	41.287802328259104
2001	39.094988154315665
2002	38.376366677878494
2003	39.11149976850165
2004	40.75189355856432
2005	43.5464470270112
2006	43.13291634975799
2007	42.81602868663481
2008	41.13372452145773
2009	41.22722584445268
2010	38.95425051577052
2011	40.42970288346997
2012	39.7020315911746
2013	39.23926192213784
2014	38.39390879649322
2015	36.18664367568768