Year	Percent
1990	57.531
1991	57.969
1992	58.168
1993	58.57
1994	59.016
1995	59.475
1996	59.908
1997	60.41
1998	60.631
1999	60.858
2000	61.077
2001	61.723
2002	62.366
2003	63.008
2004	63.643
2005	64.259
2006	64.86
2007	62.482
2008	64.17
2009	64.493
2010	64.214
2011	63.906
2012	60.058
2013	60.629
2014	62.77
2015	56.071
2016	56.6
2017	56.753
2018	56.916
2019	57.086
2020	57.262
2021	57.445
2022	57.635
2023	57.83
2024	58.03
2025	58.235
2026	58.442
2027	58.655
2028	58.87
2029	59.081
2030	59.285