Year	Percent
1990	40.979
1991	41.863
1992	42.713
1993	43.588
1994	44.653
1995	45.949
1996	46.495
1997	47.038
1998	47.292
1999	47.527
2000	48.369
2001	49.201
2002	50.013
2003	50.58
2004	50.948
2005	51.959
2006	50.379
2007	51.472
2008	52.561
2009	53.92
2010	53.285
2011	50.665
2012	52.708
2013	54.946
2014	55.117
2015	56.368
2016	57.621
2017	57.731
2018	57.847
2019	57.963
2020	58.076
2021	58.182
2022	58.286
2023	58.39
2024	58.492
2025	58.594
2026	58.689
2027	58.783
2028	58.878
2029	58.983
2030	59.101