Year	Percent
1991	10.548
1992	10.123
1993	10.364
1994	12.252
1995	13.297
1996	17.975
1997	11.714
1998	16.993
1999	13.514
2000	12.142
2001	13.943
2002	9.916
2003	12.996
2004	11.797
2005	10.107
2006	10.091
2007	10.557
2008	10.918
2009	16.79
2010	11.789
2011	12.79
2012	14.092
2013	12.169
2014	11.906
2015	11.029
2016	9.505
2017	9.137
2018	9.015
2019	8.754
2020	8.648
2021	8.517
2022	8.502