Year	Percent
1991	36.762
1992	42.615
1993	42.286
1994	42.677
1995	46.03
1996	42.505
1997	45.397
1998	46.226
1999	47.648
2000	48.504
2001	48.499
2002	41.461
2003	40.948
2004	34.233
2005	34.837
2006	32.954
2007	33.44
2008	32.368
2009	32.484
2010	34.401
2011	33.303
2012	33.405
2013	32.712
2014	31.764
2015	27.775
2016	25.022
2017	25.555
2018	25.176
2019	24.962
2020	24.786
2021	24.76
2022	24.729