Year	Percent
1991	48.014
1992	49.436
1993	49.272
1994	49.191
1995	48.178
1996	46.774
1997	46.272
1998	45.424
1999	45.425
2000	44.452
2001	44.39
2002	44.175
2003	43.858
2004	43.348
2005	43.659
2006	43.304
2007	42.421
2008	42.318
2009	42.77
2010	43.01
2011	43.267
2012	43.721
2013	43.326
2014	42.445
2015	42.823
2016	42.841
2017	43.714
2018	44.156
2019	44.435
2020	44.943
2021	45.285
2022	45.562