Year	Percent
1991	7.77
1992	8.11
1993	8.18
1994	8.023
1995	7.99
1996	7.867
1997	7.813
1998	7.545
1999	7.587
2000	7.31
2001	7.462
2002	7.486
2003	6.997
2004	6.781
2005	6.858
2006	6.929
2007	6.949
2008	6.797
2009	6.94
2010	5.344
2011	5.181
2012	5.324
2013	5.351
2014	5.05
2015	4.844
2016	4.868
2017	4.888
2018	4.891
2019	4.892
2020	4.89
2021	4.886
2022	4.881