Year	% of total
1970	2.9296605605765778
1971	2.5976731575136225
1972	2.3460600135484664
1973	2.356819599391672
1974	2.152782713065741
1975	2.2508765206454022
1976	2.0364102510273594
1977	2.250297428778442
1978	2.447902913263282
1979	2.5547068594373616
1980	3.760311961164018
1981	3.196421251773609
1982	3.3038070584878163
1983	2.955041128999975
1984	2.6030648796346156
1985	2.534643260848351
1986	2.8971173715065777
1987	2.6308805509468245
1988	2.916559893008118
1989	3.1341779779550833
1990	2.857142857142857
1991	2.941176470588235
1992	2.941176470588235
1993	2.7777777777777777
1994	2.631578947368421
1995	2.5
1996	2.5
1997	2.5
1998	2.564102564102564
1999	2.7027027027027026
2000	2.857142857142857
2001	2.7027027027027026
2002	2.631578947368421
2003	2.941176470588235
2004	5.263157894736842
2005	5.405405405405405
2006	5.714285714285714
2007	2.857142857142857
2008	2.7027027027027026