Year	Percent
1991	12.898
1992	13.495
1993	13.422
1994	13.46
1995	13.331
1996	13.611
1997	13.384
1998	13.617
1999	13.465
2000	11.613
2001	11.901
2002	12.223
2003	12.243
2004	12.21
2005	12.158
2006	12.146
2007	12.21
2008	12.983
2009	12.864
2010	12.728
2011	12.811
2012	13.041
2013	13.34
2014	13.763
2015	13.173
2016	13.419
2017	13.332
2018	13.285
2019	13.223
2020	13.196
2021	13.164
2022	13.134