Year	Percent
1991	12.519
1992	12.273
1993	11.488
1994	12.171
1995	12.912
1996	12.273
1997	13.066
1998	11.339
1999	11.428
2000	11.287
2001	10.947
2002	12.294
2003	12.17
2004	12.637
2005	13.835
2006	13.385
2007	13.173
2008	13.615
2009	12.49
2010	12.512
2011	12.514
2012	12.411
2013	11.9
2014	11.484
2015	10.814
2016	11.696
2017	12.08
2018	12.143
2019	12.082
2020	12.004
2021	11.904
2022	11.812