Year	% of total electricity output
1990	7.37341648037024
1991	5.80355302749268
1992	8.33763774104683
1993	14.4193977707536
1994	17.1066069604839
1995	18.4652641138187
1996	16.6064272805846
1997	16.2216101864048
1998	16.5824654127157
1999	15.918875644903
2000	14.9847392687837
2001	15.9498995479658
2002	16.8260275673662
2003	11.5568321177306
2004	13.5456336178595
2005	14.9145190099515
2006	15.369108188538
2007	17.6896601175964
2008	15.86578581363
2009	18.9474902581118
2010	21.6283134284882
2011	17.6718042986425
2012	19.3236373905676
2013	22.2802833695728
2014	22.9445999705319
2015	22.6794833283268
