Year	% of total
1960	2.127659574468085
1961	3.7735849056603774
1962	2.816901408450704
1963	3.846153846153846
1964	4.081632653061225
1965	3.571428571428571
1966	2.7397260273972606
1967	2.1739130434782608
1968	1.6666666666666667
1969	1.5267175572519083
1970	1.7094017094017093
1971	1.5151515151515151
1972	0.7299270072992701
1973	1.5267175572519083
1974	0.7462686567164178
1975	0.6451612903225806
1976	1.379310344827586
1977	1.2422360248447206
1978	2.9069767441860463
1979	3.6585365853658534
1980	3.804347826086957
1981	2.13903743315508
1982	2.840909090909091
1983	3.20855614973262
1984	4.901960784313726
1985	5.627705627705628
1986	5.6000000000000005
1987	4.669260700389105
1988	5.426356589147287
1989	5.555555555555556
1990	5.238571428571428
1991	4.490204081632653
1992	3.107627118644068
1993	3.704040404040404
1994	3.5601941747572816
1995	3.084392523364486
1996	2.741682242990654
1997	3.1341880341880346
1998	2.598661417322835
1999	3.384923076923077
2000	2.957258064516129
2001	2.2224242424242426
2002	2.1413138686131385
2003	2.125797101449275
2004	2.1570588235294115
2005	2.065915492957746
2006	2.494557823129252
2007	2.4777027027027025
2008	1.8541011235955058
2009	0.7143506493506493
2010	1.8450314465408804
2011	1.9762275449101796
2012	1.6592760180995476
2013	2.973243243243243
2014	1.9898449612403102
2015	2.5583720930232556
2016	2.5193129770992364