Year	Percent
1990	45.818
1991	46.562
1992	47.038
1993	47.321
1994	47.621
1995	48.081
1996	48.726
1997	49.353
1998	49.952
1999	50.514
2000	51.043
2001	51.546
2002	51.217
2003	50.864
2004	50.493
2005	52.751
2006	53.036
2007	52.264
2008	54.698
2009	55.854
2010	57.246
2011	57.756
2012	58.702
2013	60.361
2014	62.034
2015	63.721
2016	63.547
2017	63.917
2018	64.312
2019	64.7
2020	65.054
2021	65.379
2022	65.669
2023	65.926
2024	66.159
2025	66.379
2026	66.588
2027	66.782
2028	66.977
2029	67.191
2030	67.435