Year	Percent
1990	33.375
1991	33.366
1992	33.353
1993	33.349
1994	33.35
1995	33.411
1996	33.415
1997	33.446
1998	33.515
1999	33.6
2000	33.669
2001	33.752
2002	33.816
2003	33.937
2004	34.059
2005	34.181
2006	34.26
2007	36.252
2008	38.284
2009	40.349
2010	42.437
2011	44.537
2012	44.652
2013	44.759
2014	44.877
2015	45.023
2016	45.167
2017	45.525
2018	45.875
2019	46.213
2020	46.538
2021	46.852
2022	47.157
2023	47.454
2024	47.743
2025	48.025
2026	48.304
2027	48.58
2028	48.857
2029	49.14
2030	49.432