Year	Percent
1990	44.111
1991	44.683
1992	45.621
1993	46.384
1994	46.729
1995	47.732
1996	48.318
1997	49.043
1998	49.787
1999	50.345
2000	50.764
2001	51.424
2002	52.352
2003	53.324
2004	54.061
2005	54.685
2006	55.638
2007	56.248
2008	56.831
2009	57.101
2010	57.265
2011	57.456
2012	57.746
2013	58.032
2014	58.199
2015	58.296
2016	58.492
2017	58.636
2018	58.744
2019	58.804
2020	58.793
2021	58.77
2022	58.688
2023	58.571
2024	58.438
2025	58.304
2026	58.227
2027	58.153
2028	58.1
2029	58.041
2030	57.977