Year	Percent
1991	7.6
1992	8.107
1993	8.737
1994	5.455
1995	5.108
1996	5.017
1997	5.076
1998	5.198
1999	4.894
2000	4.18
2001	3.958
2002	3.939
2003	4.102
2004	4.406
2005	4.218
2006	4.25
2007	4.636
2008	4.477
2009	4.373
2010	4.305
2011	4.119
2012	4.058
2013	4.326
2014	4.135
2015	3.975
2016	3.654
2017	4.098
2018	4.046
2019	3.99
2020	3.937
2021	3.894
2022	3.835