Year	% of total
1960	11.11111111111111
1961	8.88888888888889
1962	20.833333333333336
1963	25
1964	9.615384615384617
1965	10.169491525423728
1966	5.769230769230769
1967	3.260869565217391
1968	2.4299065420560746
1969	3.324808184143222
1970	1.7605633802816898
1971	6.314432989690721
1972	7.2289156626506035
1973	17.115251897860595
1974	19.300605245460662
1975	5.806010928961748
1976	1.669877970456005
1977	1.5679442508710801
1978	0.921435499515034
1979	0.8143322475570033
1980	0.44223327805417356
1981	2.0635805911879532
1982	3.355704697986578
1983	3.255813953488372
1984	1.2844036697247707
1985	1.5089959373186304
1986	3.4686346863468636
1987	5.469462169553328
1988	7.783417935702198
1989	3.0495552731893265
1990	4.972203389830509
1991	4.805034482758621
1992	4.295401301518438
1993	4.369191489361702
1994	4.377274774774775
1995	5.568112798264642
1996	5.127584745762712
1997	5.162650103519669
1998	4.686024340770791
1999	4.792966804979253
2000	5.025438972162741
2001	5.3643886462882096
2002	5.928175519630486
2003	6.18127562642369
2004	6.042686230248306
2005	6.0192656587473
2006	7.170618811881188
2007	7.696172839506173
2008	8.43498789346247
2009	11.001
2010	12.9920964360587
2011	12.353368794326242
2012	12.265265866209262
2013	12.351999999999999
2014	18.535018181818185
2015	18.602664233576643
2016	17.91756567425569