Year	Percent
1991	11.02
1992	10.914
1993	10.87
1994	10.855
1995	10.825
1996	11.105
1997	10.877
1998	11.18
1999	10.853
2000	10.731
2001	11.395
2002	11.479
2003	11.402
2004	11.355
2005	11.396
2006	11.476
2007	11.374
2008	11.266
2009	11.136
2010	12.067
2011	12.371
2012	12.146
2013	11.929
2014	11.525
2015	11.554
2016	11.503
2017	11.619
2018	11.725
2019	11.805
2020	11.926
2021	12.047
2022	12.178