Year	Percent
1991	48.203
1992	47.86
1993	48.479
1994	48.051
1995	47.262
1996	47.552
1997	47.159
1998	46.831
1999	46.035
2000	46.048
2001	45.582
2002	45.572
2003	45.148
2004	44.893
2005	44.677
2006	44.823
2007	44.289
2008	44.074
2009	42.564
2010	42.591
2011	44.677
2012	45.328
2013	46.113
2014	45.846
2015	44.875
2016	44.654
2017	44.512
2018	44.392
2019	44.18
2020	43.859
2021	43.517
2022	43.168