Year	Percent
1984	1.69
1985	2.58
1986	3.97
1987	2.76
1988	1.62
1989	1.12
1991	1.6
1992	1.84
1993	2
1994	1.99
1995	2.53
1996	2.52
1997	1.91
1998	2.61
1999	3.91
2001	3.02
2002	4.54
2003	5.35
2004	5.22
2006	4.16
2007	3.64
2008	3.56
2009	5.58
2010	3.62
2011	3.58
2012	3.37
2013	3.63
2014	3.45
2015	3.21
2016	3.75