Year	% of total
1970	7.042151740127347
1971	6.1963859651743896
1972	6.254548740299777
1973	6.774364986068986
1974	9.408762628443137
1975	11.845210287532261
1976	9.840866896686194
1977	9.34388687650812
1978	9.461207181621894
1979	9.211681876969598
1980	9.241586149402542
1981	8.978500929511377
1982	7.345300454759291
1983	9.169029740210027
1984	9.156413896583564
1985	10.633773448834663
1986	10.290419479762845
1987	10.40117803860871
1988	8.49493525435788
1989	8.658952728452121
1990	5.555555555555555
1991	5.263157894736842
1992	7.5
1993	6.8181818181818175
1994	9.75609756097561
1995	8.16326530612245
1996	8.16326530612245
1997	8
1998	5.769230769230769
1999	5.88235294117647
2000	5.660377358490567
2001	5.357142857142857
2002	5.88235294117647
2003	5.555555555555555
2004	5.263157894736842
2005	6
2006	6.25
2007	5.88235294117647
2008	8