Year	Percent
1990	8.48
1991	7.52
1992	7.65
1993	8.09
1994	7.79
1995	7.51
1996	7.25
1997	9
1998	7.96
1999	7.49
2000	8.38
2001	7.8
2002	7.25
2003	7.86
2004	7.4
2005	7.57
2006	8.59
2007	7.84
2008	7.31
2009	6.98
2010	6.66
2011	6.36
2012	6.07
2013	5.79
2014	5.52
2015	5.26
2016	5.33
2017	5.4
2018	5.48
2019	5.59