Year	Percent
1991	51.885
1992	52.149
1993	51.84
1994	51.798
1995	51.775
1996	52.048
1997	52.18
1998	52.607
1999	52.723
2000	52.665
2001	52.66
2002	52.37
2003	52.117
2004	51.521
2005	51.129
2006	50.929
2007	50.653
2008	50.426
2009	50.076
2010	49.488
2011	49.68
2012	49.645
2013	47.403
2014	47.561
2015	47.13
2016	47.279
2017	47.187
2018	47.172
2019	47.099
2020	46.964
2021	46.786
2022	46.866