Year	Percent
1983	0.29
1984	0.35
1985	0.49
1986	1.2
1987	1.9
1988	0.66
1989	0.59
1990	0.56
1991	1.24
1992	1.04
1993	0.91
1994	1.16
1995	0.94
1996	1.32
1997	1.4
1998	1.09
1999	1.18
2000	0.79
2001	0.49
2002	0.45
2003	0.87
2004	0.81
2007	1.05
2008	0.93
2009	0.94
2011	0.9
2012	0.85
2013	0.85
2014	0.82
2015	0.82
2016	0.68
2017	0.78
2018	0.74
2019	0.79