Year	% of total electricity output
1990	27.78885227458887
1991	26.15613632369156
1992	24.31774267444875
1993	22.766267627351446
1994	24.635256121636136
1995	20.891266809795443
1996	18.834072987276173
1997	18.955009503513445
1998	19.40491022600292
1999	17.49088394316614
2000	15.42246950655929
2001	15.249300950822894
2002	14.543019906128896
2003	16.227623910218153
2004	16.549828477208475
2005	18.776675251298677
2006	19.684327693774527
2007	19.632854939686542
2008	18.417139254685562
2009	17.454492833452782
2010	18.17933245987069
2011	18.719759983729436
2012	17.194764154073823
2013	18.871312109698312
2014	17.618236196469983
2015	16.86779926197486