Year	Percent
1991	64.437
1992	62.499
1993	64.24
1994	64.138
1995	63.656
1996	63.545
1997	62.059
1998	66
1999	66.747
2000	59.992
2001	58.548
2002	59.935
2003	59.968
2004	59.921
2005	60.423
2006	59.462
2007	59.487
2008	60.285
2009	59.291
2010	59.514
2011	58.877
2012	59.03
2013	57.786
2014	57.124
2015	57.758
2016	58.076
2017	58.122
2018	58.076
2019	58.029
2020	57.981
2021	57.934
2022	57.89