Year	Percent
1991	10.554
1992	9.939
1993	9.38
1994	8.819
1995	8.699
1996	8.015
1997	8.02
1998	8.044
1999	8.299
2000	8.486
2001	7.907
2002	8.004
2003	8.192
2004	8.278
2005	8.413
2006	8.559
2007	8.725
2008	8.534
2009	8.69
2010	13.274
2011	13.391
2012	13.153
2013	12.259
2014	9.293
2015	9.614
2016	9.95
2017	10.049
2018	10.044
2019	10.068
2020	10.094
2021	10.164
2022	10.263