Year	Percent
1991	14.048
1992	13.831
1993	14.051
1994	12.256
1995	12.234
1996	12.02
1997	12.389
1998	12.584
1999	12.14
2000	12.107
2001	12.522
2002	12.154
2003	12.085
2004	11.942
2005	11.953
2006	11.937
2007	12.289
2008	12.272
2009	12.93
2010	12.336
2011	12.444
2012	12.372
2013	12.127
2014	11.9
2015	11.584
2016	11.862
2017	11.931
2018	11.857
2019	11.784
2020	11.714
2021	11.645
2022	11.586