Year	Percent
1991	9.076
1992	9.114
1993	8.926
1994	9.014
1995	9.001
1996	9.541
1997	9.678
1998	9.729
1999	10.215
2000	9.878
2001	9.787
2002	10.029
2003	10.077
2004	8.947
2005	8.297
2006	8.295
2007	8.558
2008	8.753
2009	9.322
2010	9.213
2011	10.051
2012	10.846
2013	10.136
2014	10.069
2015	10.02
2016	10.037
2017	10.306
2018	10.486
2019	10.63
2020	10.792
2021	10.952
2022	11.072