Year	Percent
1990	42.393
1991	42.138
1992	41.942
1993	41.756
1994	41.773
1995	41.953
1996	42.385
1997	43.89
1998	45.407
1999	46.932
2000	48.456
2001	49.973
2002	51.48
2003	52.977
2004	54.47
2005	55.961
2006	57.447
2007	58.003
2008	58.569
2009	59.145
2010	59.726
2011	60.31
2012	60.894
2013	61.473
2014	62.042
2015	62.883
2016	63.715
2017	64
2018	64.285
2019	64.57
2020	64.856
2021	65.143
2022	65.432
2023	65.721
2024	66.009
2025	66.295
2026	66.579
2027	66.861
2028	67.142
2029	67.423
2030	67.704