Year	Percent
1991	62.484
1992	62.294
1993	59.765
1994	59.481
1995	60.773
1996	62.187
1997	63.403
1998	66.152
1999	62.665
2000	63.83
2001	58.854
2002	63.654
2003	57.765
2004	59.439
2005	60.693
2006	64.213
2007	64.029
2008	65.245
2009	62.719
2010	59.452
2011	58.435
2012	55.249
2013	54.934
2014	54.799
2015	56.133
2016	59.972
2017	59.823
2018	59.961
2019	59.608
2020	59.339
2021	59.004
2022	58.617