Year	Percent
1991	51.548
1992	51.587
1993	51.525
1994	51.349
1995	51.032
1996	50.859
1997	50.525
1998	50.098
1999	49.622
2000	49.131
2001	48.817
2002	49.018
2003	49.206
2004	49.372
2005	49.563
2006	50.066
2007	50.506
2008	49.942
2009	49.377
2010	49.071
2011	48.606
2012	48.104
2013	47.558
2014	46.958
2015	46.716
2016	46.504
2017	46.435
2018	46.351
2019	46.269
2020	46.19
2021	46.112
2022	46.033