Year	Percent
1991	8.756
1992	9.452
1993	9.534
1994	10.367
1995	9.575
1996	8.692
1997	8.611
1998	8.838
1999	8.939
2000	9.723
2001	9.722
2002	9.713
2003	10.169
2004	10.396
2005	10.905
2006	11.555
2007	11.981
2008	11.53
2009	11.111
2010	11.426
2011	11.417
2012	11.603
2013	12.183
2014	11.973
2015	11.473
2016	11.678
2017	11.627
2018	11.592
2019	11.543
2020	11.472
2021	11.385
2022	11.312