Year	Percent
1974	0.26
1975	0.32
1976	0.5
1977	0.71
1978	0.54
1979	0.72
1980	0.8
1981	1.02
1982	3.03
1983	3.3
1984	3.4
1985	5.87
1986	3.94
1987	7.53
1988	3.52
1989	1.55
1990	2.41
1991	3.4
1992	1.49
1993	1.82
1994	1.6216
1995	1.34
1996	1.11583
1997	0.90457
1998	3.3967
1999	2.93806
2000	2.33412
2001	2.49
2002	1.63
2003	1.44
2004	1.38
2005	1.21
2006	1.12
2007	1.06
2008	1.04
2009	1.45
2010	0.6222
2011	0.68
2012	0.53
2013	0.4761
2014	0.5643
2015	0.6062
2016	0.7143