Year	Percent
1991	5.43
1992	5.39
1993	5.37
1994	7.1
1995	11.33
1996	9.24
1997	7.38
1998	6.44
1999	4.09
2000	5.08
2001	4.85
2002	6.13
2003	7.12
2004	8.2
2005	6.92
2006	7.04
2007	7.17
2008	7.65
2009	10.07
2010	9.73
2011	9.79
2012	9.38
2013	9.42
2014	9.44
2015	8.56
2016	7.67
2017	6.87
2018	6.86
2019	7.19
2020	8.12