Year	% of total
1960	42.518837459634014
1961	35.91800356506239
1962	38.24561403508772
1963	26.593557230980124
1964	23.739919354838708
1965	15.928927680798004
1966	13.125
1967	5.76978006283919
1968	0.11055831951354339
1969	0.48440811383590676
1970	0.8001361933946204
1971	1.703964557537203
1972	2.0713463751438432
1973	1.6198224852071008
1974	1.2421263319008653
1975	1.253384912959381
1976	1.3872295234302403
1977	1.3923132704858592
1978	1.1237661351556567
1979	0.6521285475792988
1980	0.6994511998278274
1981	0.4336465224884639
1982	0.24594745667970933
1983	0.2569907605702747
1984	0.28967188076052036
1985	0.5299055613850997
1986	0.4040907957096533
1987	0.34604214298955693
1988	0.2280619913958431
1989	0.336962156557802
1990	0.24320560058953572
1991	0.2523276432446738
1992	0.1612800925925926
1993	0.026065632034119178
1994	0.08196448528498697
1995	0.06296051017905323
1996	0.025237439779766002
1997	0.030726598036868568
1998	0.043062369519832985
1999	0.058939190999196346
2000	0.009641120021033258
2001	0.00861303581914269
2002	0.13201370340262455
2003	0.07029657194406856
2004	0.024824551506261984
2005	0.02235067045916294
2006	0.023863340563991323
2007	0.06916564961721956
2008	0.09214574456462361
2009	0.12348464439655173
2010	0.11316653808001763
2011	0.08261435987853855
2012	0.12747814858959078
2013	0.10598265895953755
2014	0.10414027538726335
2015	0.11528247803975959
2016	0.1116131710016602