Year	% of output
1971	24.646464646464647
1972	28.368794326241137
1973	19.508196721311474
1974	9.597523219814242
1975	9.855072463768117
1976	12.817089452603472
1977	13.840399002493767
1978	13.988439306358384
1979	21.680497925311204
1980	14.075887392900857
1981	20.09512485136742
1982	20.42175360710322
1983	25.29474812433012
1984	3.2225579053373616
1985	14.157851912123679
1986	10.46337817638266
1987	9.934735315445975
1988	18.79535558780842
1989	21.245421245421245
1990	15.37953795379538
1991	23.901264298615292
1992	20.746634026927786
1993	24.67378410438909
1994	27.664155005382128
1995	26.98497854077253
1996	31.555986427532716
1997	36.7906976744186
1998	31.129196337741604
1999	15.270326042096574
2000	15.531335149863759
2001	34.225352112676056
2002	27.48140963465891
2003	27.489564698867024
2004	27.487741563311218
2005	20.491374803972818
2006	23.114355231143552
2007	23.441545508862777
2008	21.92154013803124
2009	21.92266214758897
2010	19.30924123216429
2011	20.544056771141335
2012	19.012293344637555
2013	22.909373784519644
2014	14.284458509142054