Year	% of total
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	1.997501456345048
1985	2.5436987467039542
1986	4.045086292254063
1987	2.754263315587501
1988	4.4832224851589375
1989	4.57104226351984
1990	3.383988903645236
1991	3.611090163535885
1992	3.6836519893338844
1993	2.7884661450862294
1994	3.613641164204152
1995	4.07156278879066
1996	4.01056320018371
1997	4.153800215650301
1998	4.4958714949930085
1999	4.194846992153643
2000	4.095939508514757
2001	3.2951474716113704
2002	3.4623722012970233
2003	3.5452968376514695
2004	3.53100356764645
2005	2.9332176310221096
2006	2.503565853619285
2007	2.740809722234204
2008	3.1845383027634093
2009	3.1766483390690055
2010	2.8197095725627084
2011	3.065807764699335
2012	2.7065643350670014
2013	3.1319852571907956
2014	2.990167271419937