Year	Percent
1989	0.56
1990	0.64
1991	1.47
1992	3.68
1993	6.54
1994	7.56
1995	9.66
1996	9.92
1997	10.37
1998	9.51
1999	11.57
2000	13.36
2001	13.13
2002	10.03
2003	11.29
2004	10.25
2005	8.03
2006	5.91
2007	4.59
2008	5.45
2009	13.55
2010	16.71
2011	12.33
2012	10.02
2013	8.63
2014	7.35
2015	6.19
2016	6.76
2017	5.76
2018	5.37
2019	4.45
2020	6.8