Year	Percent
1991	10.849
1992	10.758
1993	10.783
1994	9.88
1995	9.584
1996	9.377
1997	9.49
1998	9.744
1999	9.325
2000	9.17
2001	8.913
2002	8.926
2003	9.172
2004	8.805
2005	8.919
2006	9.085
2007	9.041
2008	8.873
2009	9.377
2010	9.135
2011	9.145
2012	9.155
2013	9.036
2014	8.906
2015	8.677
2016	9.084
2017	9.154
2018	9.081
2019	9.013
2020	8.948
2021	8.886
2022	8.832