Year	Percent
1991	57.519
1992	57.533
1993	57.656
1994	57.329
1995	57.473
1996	57.4
1997	57.184
1998	57.06
1999	57.112
2000	56.892
2001	57.267
2002	57.677
2003	57.607
2004	57.621
2005	57.556
2006	57.264
2007	57.206
2008	57.127
2009	57.268
2010	57.459
2011	57.56
2012	57.608
2013	57.654
2014	57.705
2015	57.889
2016	57.828
2017	57.85
2018	57.892
2019	57.921
2020	57.92
2021	57.845
2022	57.751