Year	Percent
1990	8.79
1991	9
1992	11.35
1993	14.88
1994	19.06
1995	22.21
1996	22.25
1997	21.24
1998	19.45
1999	18.27
2000	16.58
2001	15.23
2002	13.74
2003	14.23
2004	9.74
2005	10.47
2006	8.28
2007	7.68
2008	8.66
2009	5.09
2010	6.62
2011	8.28
2012	5.8
2013	4.86
2014	4
2015	5.92
2016	6.22
2017	6.21
2018	6.33
2019	6.3