Year	% of total
1960	1.1351636747624076
1961	1.1791128579449746
1962	0.9290396124251924
1963	0.7654688496704232
1964	0.5595834752566785
1965	1.2690710586478795
1966	1.320204874602614
1967	1.0046009032966106
1968	0.9221466364323506
1969	0.7886164923709925
1970	0.8059496117681747
1971	0.4031651472756265
1972	0.48569886670264434
1973	0.4210267142681275
1974	0.5671881646736304
1975	0.4483316184036455
1976	0.23130955159900687
1977	0.47792784143036976
1978	0.4410688502541585
1979	0.45082362007513727
1980	0.5236292403608898
1981	0.7612235519769835
1982	0.6662931689943575
1983	0.6477857679924425
1984	0.6537530266343826
1985	0.510140599726266
1986	0.5952690859235348
1987	0.688305228873522
1988	0.5562355711873074
1989	0.4560611271438611
1990	0.3784214419848631
1991	0.32169246762003767
1992	0.477524156280633
1993	0.36250499514757095
1994	0.4849946033837485
1995	0.4597638609282333
1996	0.3180813968963773
1997	0.391723712770193
1998	0.4739567468778556
1999	0.40903965645466983
2000	0.5557367740688389
2001	0.5609402426925132
2002	0.4447794017717046
2003	0.2955924414499587
2004	0.3758016905148602
2005	0.33602072127781213
2006	0.4256176791388059
2007	0.44442921122383694
2008	0.49053037100845864
2009	0.36523172171124424
2010	0.33250562168959746
2011	0.22019008245893903
2012	0.43738743705663985
2013	0.4624896548366681
2014	0.40838018516964564
2015	0.45723816644619547