Year	Percent
1991	13.155
1992	12.929
1993	12.981
1994	12.903
1995	12.558
1996	12.43
1997	12.187
1998	11.834
1999	11.485
2000	11.3
2001	11.153
2002	11.079
2003	11.235
2004	11.184
2005	11.006
2006	10.872
2007	10.65
2008	10.431
2009	10.557
2010	10.62
2011	10.354
2012	10.299
2013	10.088
2014	9.935
2015	9.942
2016	9.86
2017	9.805
2018	9.748
2019	9.658
2020	9.607
2021	9.566
2022	9.527