Year	Percent
1974	8.1
1982	7.3
1986	12.12
1987	11.4
1990	4.78
1991	4.58
1992	3.06
1995	3.24
1996	4.37
1997	3.32
1998	4.02
1999	3.85
2001	4
2002	4.02
2003	5.3
2004	5.99
2005	4.91
2006	3.57
2007	3.21
2008	3.16
2009	3.29
2010	4.12
2011	4.47
2012	3.75
2013	5.65
2014	7.08
2015	6.15
2016	6.73
2017	5.53
2018	5.65
2019	5.7
2020	10.98