Year	Percent
1991	26.327
1992	22.865
1993	24.14
1994	22.868
1995	25.645
1996	25.48
1997	24.474
1998	29.973
1999	33.08
2000	32.997
2001	33.665
2002	31.646
2003	31.651
2004	30.151
2005	28.948
2006	27.743
2007	27.339
2008	27.456
2009	24.872
2010	25.689
2011	27.795
2012	26.626
2013	26.449
2014	26.588
2015	25.595
2016	25.302
2017	25.364
2018	25.313
2019	25.053
2020	25.026
2021	25.085
2022	25.102