Year	% of output
1971	15.373507893723527
1972	13.186642906949718
1973	12.903925395792669
1974	12.005440889467147
1975	11.894695304132139
1976	11.565351977370977
1977	11.23091603053435
1978	12.23090569113487
1979	13.338483912015997
1980	13.344453711426189
1981	13.435288169868555
1982	13.569356697262288
1983	14.162908137697082
1984	14.005405205286735
1985	15.13284691629956
1986	14.06013774567445
1987	16.271290575826878
1988	17.513260225830596
1989	17.118873204011695
1990	18.741482490964035
1991	19.59215424793021
1992	18.205171635049684
1993	15.865957277852775
1994	15.65449269300149
1995	15.501936539247998
1996	15.839350180505415
1997	15.648558505048658
1998	14.281465619795384
1999	13.90418901290042
2000	15.013713028197927
2001	15.363588310805708
2002	14.387772528035521
2003	14.297136925386114
2004	14.830878137540816
2005	14.447848888582872
2006	13.566980479315623
2007	13.88239241343241
2008	17.199470349002176
2009	16.44750665359294
2010	15.002887047323178
2011	16.306299452221545
2012	15.97631459655485
2013	16.30609077977499
2014	15.966022156880216