Year	Percent
1991	8.925
1992	9.118
1993	9.053
1994	8.852
1995	8.765
1996	8.589
1997	8.568
1998	8.488
1999	8.202
2000	8.196
2001	8.363
2002	8.244
2003	8.161
2004	8.367
2005	8.922
2006	9.226
2007	10.355
2008	10.645
2009	10.209
2010	10.061
2011	9.78
2012	9.905
2013	9.798
2014	9.14
2015	8.992
2016	9.062
2017	8.972
2018	8.916
2019	8.83
2020	8.743
2021	8.674
2022	8.613