Year	% of output
1971	16.89189189189189
1972	16.463414634146343
1973	16.577540106951872
1974	14.903846153846153
1975	15.625
1976	16.296296296296298
1977	16.233766233766232
1978	17.142857142857142
1979	17.183098591549296
1980	18.591549295774648
1981	19.88950276243094
1982	19.55922865013774
1983	18.598382749326145
1984	19.736842105263158
1985	18.367346938775512
1986	18.678815489749432
1987	17.453798767967147
1988	17.272727272727273
1989	13.921901528013583
1990	8.974358974358974
1991	8.98483080513419
1992	9.032258064516128
1993	8.998988877654195
1994	8.969465648854962
1995	9.005145797598628
1996	9.03377847604085
1997	9.006433166547534
1998	9.037711313394018
1999	9.022082018927446
2000	8.998875140607424
2001	9.000523286237572
2002	8.974358974358974
2003	8.981748318924112
2004	8.960739030023095
2005	8.97887323943662
2006	8.46808510638298
2007	8.640973630831644
2008	8.44739929605006
2009	7.683352735739232
2010	7.21457791000372
2011	7.10362504577078
2012	6.828745084018592
2013	6.3711911357340725
2014	6.196799455226421