Year	Percent
1991	56.254
1992	55.114
1993	55.575
1994	55.737
1995	47.224
1996	47
1997	46.59
1998	41.676
1999	41.765
2000	42.925
2001	41.653
2002	32.894
2003	33.131
2004	32.082
2005	45.319
2006	44.14
2007	43.038
2008	42.119
2009	43.228
2010	43.058
2011	44.204
2012	44.03
2013	45.001
2014	41.535
2015	35.061
2016	35.343
2017	35.334
2018	35.296
2019	35.242
2020	35.186
2021	35.131
2022	35.078