Year	% of output
1971	4.545454545454546
1972	5.88235294117647
1973	6.25
1974	5.05050505050505
1975	5.714285714285714
1976	6.140350877192982
1977	8.653846153846153
1978	24.242424242424242
1979	10
1980	9.032258064516128
1981	31.0126582278481
1982	12.307692307692308
1983	41.02564102564102
1984	14.229249011857709
1985	49.65986394557823
1986	10
1987	13.87900355871886
1988	22.602739726027394
1989	17.75
1990	19.675456389452332
1991	18.75
1992	21.49532710280374
1993	31.215469613259668
1994	25.617283950617285
1995	31.07344632768362
1996	27.074235807860266
1997	26.71081677704194
1998	41.56976744186046
1999	82.88288288288288
2000	87.5
2001	88.02395209580838
2006	86.75496688741721
2008	76.78958785249458
2009	70.31539888682747
2010	59.43877551020408
2011	51.89481825212684
2012	44.529411764705884
2013	44.52896430661205
2014	44.54022988505747