Year	Percent
1991	44.813
1992	30.953
1993	44.15
1994	55.771
1995	56.945
1996	54.567
1997	50.874
1998	58.945
1999	56.888
2000	57.206
2001	58.656
2002	60.592
2003	59.243
2004	56.473
2005	57.285
2006	55.847
2007	55.193
2008	50.202
2009	43.094
2010	43.001
2011	43.858
2012	43.111
2013	42.678
2014	44.756
2015	42.809
2016	41.215
2017	43.974
2018	43.712
2019	43.727
2020	43.738
2021	43.823
2022	44.02