Year	Percent
1991	11.51895
1992	11.48216
1993	11.39699
1994	11.27328
1995	11.12948
1996	10.94754
1997	10.7429
1998	10.54267
1999	10.28268
2000	9.9255
2001	9.31929
2002	8.7115
2003	8.14077
2004	7.57043
2005	7.01953
2006	6.50153
2007	6.01416
2008	5.57021
2009	5.05152
2010	4.84912
2011	4.59468
2012	4.83064
2013	4.98142
2014	4.64634
2015	5.60563
2016	5.56691
2017	5.28122
2018	5.16046
2019	5.2845