Year	% of total
1960	0
1961	0
1962	0
1963	0
1964	0
1965	0
1966	0
1967	0
1968	0
1969	0
1970	0
1971	0
1972	0
1973	0
1974	0
1975	0
1976	0
1977	0
1978	0
1979	0
1980	0
1981	0
1982	0
1983	0
1984	0
1985	0
1986	0
1987	0.0033238050920694007
1988	0.0030154996682950365
1989	0.0029231218941829875
1990	0.005751258087706686
1991	0.005595501217021515
1992	0.0241773002014775
1993	0.12586202375645697
1994	0.09410366261360541
1995	0.08474781471706337
1996	0.08959939638301384
1997	0.08315624133789153
1998	0.151580770896492
1999	0.3299929142625772
2000	0.8441740758072063
2001	1.573215766071294
2002	1.4403559180646957
2003	1.9445643726793889
2004	2.118579225681397
2005	2.3373214195567673
2006	3.01434055069044
2007	3.1940169986126836
2008	3.875254323499491
2009	4.601106491635839
2010	5.337563407533948
2011	6.983032515378895
2012	9.458458804363925
2013	14.012326224743497
2014	15.297062153626126
2015	16.888580139709003