Year	% of output
1971	3.644646924829157
1972	3.655483224837256
1973	17.088607594936708
1974	7.069555302166476
1975	6.254180602006689
1976	3.686274509803922
1977	3.6809815950920246
1978	9.024241189651661
1979	10.159651669085632
1980	9.25086643561717
1981	8.318810270709887
1982	10.244040862656073
1983	13.75722543352601
1984	15.284099251211275
1985	6.660519222584764
1986	20.541344132875377
1987	22.01088139281828
1988	17.00329352009841
1989	11.581757829412613
1990	9.743778124713014
1991	12.02731655061596
1992	12.11427745525498
1993	10.522026431718063
1994	9.363682386385763
1995	12.293683374723363
1996	12.274821333648338
1997	9.957522076460263
1998	12.711755811271432
1999	13.309666530873537
2000	11.513527993570854
2001	12.862701720425859
2002	16.144413539462377
2003	16.369253102483757
2004	11.852234048750447
2005	11.163735307263446
2006	11.073704460743055
2007	10.720290395424584
2008	10.108085664921045
2009	9.59853036855601
2010	9.39825041972254
2011	9.089669986969582
2012	8.922161675748638
2013	9.582908989908342
2014	9.401165546174235
