Year	Percent
1991	8.411
1992	11.281
1993	11.764
1994	10.755
1995	10.005
1996	10.321
1997	12.047
1998	11.47
1999	11.004
2000	13.268
2001	12.254
2002	13.86
2003	13.545
2004	16.165
2005	16.703
2006	16.432
2007	16.168
2008	15.794
2009	15.339
2010	15.96
2011	15.24
2012	14.954
2013	15.393
2014	17.184
2015	16.252
2016	15.982
2017	15.949
2018	16.017
2019	16.13
2020	16.18
2021	16.19
2022	16.177