Year	Percent
1991	14.83
1992	10.419
1993	10.483
1994	10.801
1995	10.585
1996	11.196
1997	11.737
1998	12.484
1999	11.53
2000	11.537
2001	11.834
2002	11.561
2003	12.099
2004	11.781
2005	11.167
2006	11.38
2007	11.386
2008	10.905
2009	11.241
2010	11.455
2011	11.487
2012	12.571
2013	12.417
2014	10.856
2015	9.557
2016	8.932
2017	8.838
2018	8.64
2019	8.456
2020	8.315
2021	8.176
2022	8.053