Year	Percent
1990	12.21
1991	11.99
1992	11.59
1993	11.52
1994	11.63
1995	11.41
1996	11.37
1997	10.72
1998	10.42
1999	10.51
2000	9.97
2001	9.68
2002	10.26
2003	11.23
2004	11.34
2005	11.47
2006	11.29
2007	11.12
2008	10.97
2009	10.84
2010	10.74
2011	10.48
2012	10.21
2013	9.92
2014	9.62
2015	9.32
2016	9.28
2017	9.71
2018	9.92
2019	10.22