Year	Percent
1990	53.696
1991	53.473
1992	53.333
1993	53.717
1994	54.789
1995	55.427
1996	56.762
1997	58.281
1998	55.813
1999	56.378
2000	57.742
2001	58.31
2002	59.007
2003	58.369
2004	59.621
2005	60.323
2006	61.431
2007	61.883
2008	62.141
2009	61.421
2010	62.117
2011	62.747
2012	62.874
2013	63.461
2014	64.803
2015	65.449
2016	66.045
2017	66.254
2018	66.474
2019	66.689
2020	66.89
2021	67.08
2022	67.262
2023	67.434
2024	67.589
2025	67.721
2026	67.824
2027	67.892
2028	67.936
2029	67.98
2030	68.042