Year	Percent
1982	10.93
1983	12.06
1984	11.92
1985	11.21
1988	8.04
1989	8.26
1990	8.02
1991	8.21
1992	8.51
1993	8.96
1994	8.58
1995	7.64
1996	6.63
1997	6.84
1998	6.89
1999	7.69
2000	6.5
2001	8.38
2002	10.36
2003	10.54
2004	10.84
2005	10.64
2006	8.72
2007	8.87
2008	9.71
2009	12.55
2010	10.66
2011	8.8
2012	8.15
2013	8.73
2014	9.88
2015	10.24
2016	10.84
2017	10.82
2018	10.89
2019	13.67
2020	13.11