Year	Percent
1975	1.05
1976	1.11
1982	2.21
1983	2.42
1984	2.13
1985	1.94
1986	1.66
1987	1.61
1989	1.13
1990	1.27
1991	2.52
1992	4.77
1993	7.88
1994	8.11
1995	7.67
1996	8.22
1997	9.11
1998	8.39
1999	6.7
2000	4.95
2001	3.69
2002	3.92
2003	4.46
2004	5.3
2005	5.98
2006	5.3
2007	4.41
2008	4.31
2009	6.19
2010	6.46
2011	5.75
2012	5.92
2013	6.07
2014	5.98
2015	5.79
2016	5.49
2017	5.37
2018	5.16
2019	5.35
2020	6.76