Year	Percent
1991	7.953
1992	7.499
1993	7.403
1994	8.068
1995	7.959
1996	7.757
1997	11.706
1998	12.373
1999	11.684
2000	11.143
2001	11.331
2002	11.402
2003	11.284
2004	10.968
2005	10.714
2006	10.648
2007	10.647
2008	10.493
2009	10.789
2010	10.627
2011	10.569
2012	10.44
2013	10.543
2014	10.579
2015	10.753
2016	10.967
2017	11.165
2018	11.145
2019	11.13
2020	11.114
2021	11.101
2022	11.088