Year	Percent
1991	47.713
1992	47.992
1993	47.866
1994	48.214
1995	47.743
1996	45.91
1997	45.559
1998	45.4
1999	45.127
2000	46.572
2001	47.212
2002	47.596
2003	46.84
2004	46.67
2005	46.483
2006	45.363
2007	45.759
2008	45.552
2009	42.99
2010	41.331
2011	42.272
2012	40.801
2013	42.079
2014	42.626
2015	45.165
2016	43.437
2017	43.119
2018	42.996
2019	42.821
2020	42.613
2021	42.3
2022	41.959