Year	Percent
1991	50.137
1992	51.733
1993	52.217
1994	53.314
1995	54.507
1996	55.362
1997	57.427
1998	59.128
1999	60.582
2000	61.803
2001	64.459
2002	61.708
2003	59.073
2004	61.977
2005	61.502
2006	64.73
2007	69.908
2008	67.58
2009	67.112
2010	65.3
2011	65.795
2012	65.954
2013	67.468
2014	66.801
2015	64.954
2016	65.305
2017	65.538
2018	65.874
2019	66.24
2020	66.573
2021	66.856
2022	67.088