Year	Percent
1991	37.404
1992	36.257
1993	33.569
1994	33.484
1995	33.731
1996	34.21
1997	33.104
1998	33.183
1999	30.328
2000	27.573
2001	26.018
2002	27.2
2003	23.224
2004	29.058
2005	30.002
2006	30.964
2007	32
2008	33.475
2009	31.178
2010	30.369
2011	26.976
2012	24.19
2013	23.162
2014	23.921
2015	26.737
2016	25.668
2017	25.946
2018	25.797
2019	25.542
2020	25.192
2021	24.779
2022	24.317