Year	Percent
1991	32.218
1992	29.159
1993	28.797
1994	28.095
1995	27.369
1996	27.737
1997	25.574
1998	26.619
1999	25.291
2000	25.771
2001	24.603
2002	23.312
2003	23.802
2004	25.447
2005	24.557
2006	25.778
2007	25.826
2008	25.503
2009	25.264
2010	25.252
2011	23.436
2012	25.159
2013	26.145
2014	24.878
2015	26.114
2016	25.636
2017	25.623
2018	25.598
2019	25.577
2020	25.559
2021	25.54
2022	25.522