Year	Percent
1986	1.6
1987	1.52
1988	1.6
1989	3.41
1990	2.15
1991	2.22
1992	1.45
1993	1.47
1994	1.25
1995	1.26
1996	0.74
1997	0.78
1998	0.8
1999	1.33
2000	1.52
2001	1.06
2002	1.42
2003	1.13
2004	0.78
2005	1.46
2006	1.93
2007	0.85
2008	1.28
2009	1.33
2010	1.97
2011	1.72
2012	1.66
2013	1.62
2014	1.53
2015	1.55
2016	1.17
2017	1.15
2018	1.65
2019	1.42
2020	1.89