Year	Percent
1991	27.734
1992	27.484
1993	27.357
1994	27.188
1995	26.901
1996	26.929
1997	27.047
1998	27.34
1999	27.813
2000	28.278
2001	28.667
2002	27.355
2003	26.566
2004	24.234
2005	23.126
2006	25.155
2007	24.6
2008	25.121
2009	23.466
2010	24.538
2011	24.277
2012	23.398
2013	24.233
2014	25.393
2015	25.716
2016	26.186
2017	25.758
2018	25.698
2019	25.654
2020	25.918
2021	26.334
2022	26.934