Year	% of total electricity output
1990	21.61853752224875
1991	21.706047607394467
1992	21.483040024371274
1993	21.63332362569354
1994	22.788039025247027
1995	20.758994310530746
1996	20.188629214534465
1997	19.37806673612877
1998	19.954286282554676
1999	19.45125530464802
2000	17.995437691099863
2001	18.032168542047575
2002	17.071142499269712
2003	17.91012539882013
2004	17.961183915537788
2005	18.865454607118874
2006	19.26711161564058
2007	18.842461413803644
2008	17.964580924655568
2009	17.615052885727966
2010	17.88897713701116
2011	18.26568279480199
2012	17.68392013446006
2013	18.67290253577732
2014	17.890267636081035
2015	17.24705769254246
