Year	% of total electricity output
1990	17.744017167115
1991	25.6817421615056
1992	21.5923978226774
1993	23.0171605739419
1994	23.6614915844457
1995	28.166233590929
1996	25.680521597392
1997	30.6572408483237
1998	35.3110512935547
1999	36.0678367185959
2000	28.4553471714099
2001	27.7039319793562
2002	29.3212752352243
2003	24.0515052593399
2004	29.2341457370927
2005	34.0211738171781
2006	29.283697784583
2007	25.949767321194
2008	26.5164111090584
2009	26.9357995185397
2010	33.4878503439516
2011	26.3149405635575
2012	25.3955830809542
2013	34.4215525488588
2014	41.6060857028926
2015	39.7469736961864