Year	Percent
1991	9.388
1992	9.988
1993	10.275
1994	10.472
1995	10.086
1996	10.123
1997	9.841
1998	9.726
1999	9.351
2000	9.343
2001	9.655
2002	9.52
2003	9.668
2004	10.253
2005	8.107
2006	8.36
2007	8.509
2008	6.262
2009	6.933
2010	8.986
2011	9.531
2012	9.344
2013	9.246
2014	9.306
2015	9.04
2016	8.502
2017	8.309
2018	8.057
2019	7.756
2020	7.46
2021	7.192
2022	6.93