Year	Percent
1991	39.001
1992	39.979
1993	39.608
1994	43.357
1995	39.798
1996	36.699
1997	24.415
1998	24.246
1999	24.33
2000	24.597
2001	35.082
2002	35.61
2003	35.168
2004	34.505
2005	30.129
2006	29.019
2007	28.175
2008	27.292
2009	26.631
2010	24.368
2011	23.895
2012	24.595
2013	24.718
2014	24.303
2015	25.183
2016	25.503
2017	25.464
2018	25.422
2019	25.336
2020	25.238
2021	25.155
2022	25.08