Year	% of total
1970	3.354703151789799
1971	3.5683412553392744
1972	3.6377839783693147
1973	3.2333001738435017
1974	3.359531485901897
1975	3.419489232283024
1976	3.0937644124112538
1977	3.323204214817098
1978	3.11308303883283
1979	3.265365616813629
1980	4.454580411239921
1981	5.055543946602654
1982	4.723090054386056
1983	4.337811120503429
1984	7.774518160663699
1985	8.997968594876253
1986	13.821847264375359
1987	13.6463475921442
1988	13.628092638106029
1989	14.154740193255263
1991	0
1992	0
1993	0
1994	0
1995	0
1996	0
1997	100
1998	100
1999	100
2000	100
2001	100
2002	100
2003	100
2004	100
2005	100
2006	50
2007	50
2008	50