Year	Percent
1991	12.692
1992	12.681
1993	12.857
1994	13.154
1995	11.021
1996	11.244
1997	9.579
1998	8.875
1999	9.601
2000	8.899
2001	8.928
2002	9.023
2003	8.778
2004	8.33
2005	8.506
2006	8.485
2007	8.27
2008	8.597
2009	9.067
2010	9.005
2011	8.824
2012	8.899
2013	8.83
2014	9.359
2015	9.484
2016	9.408
2017	9.457
2018	9.396
2019	9.344
2020	9.307
2021	9.274
2022	9.245