Year	Percent
1991	12.171
1992	13.199
1993	11.353
1994	12.315
1995	11.319
1996	10.748
1997	10.482
1998	10.563
1999	10.499
2000	10.422
2001	10.14
2002	10.674
2003	11.171
2004	10.594
2005	10.422
2006	11.191
2007	11.785
2008	10.864
2009	10.444
2010	10.2
2011	9.919
2012	9.626
2013	9.707
2014	9.707
2015	9.835
2016	9.938
2017	9.983
2018	9.999
2019	9.982
2020	9.958
2021	9.932
2022	9.937