Year	Percent
1990	10.31
1991	10.7
1992	10.47
1993	10.43
1994	10.68
1995	10.02
1996	10.33
1997	10.78
1998	10.38
1999	10.2
2000	10.25
2001	10.67
2002	10.83
2003	12.33
2004	10.91
2005	11.4
2006	10.05
2007	10.73
2008	12.12
2009	12.18
2010	12.68
2011	11.07
2012	9.47
2013	8.16
2014	7.22
2015	7.01
2016	7.43
2017	7.65
2018	8.4
2019	9.27