Year	Percent
1990	49.896
1991	50.134
1992	50.471
1993	50.666
1994	50.995
1995	51.242
1996	51.404
1997	51.676
1998	51.848
1999	51.963
2000	52.103
2001	52.203
2002	52.301
2003	52.376
2004	52.443
2005	52.494
2006	52.552
2007	52.605
2008	52.659
2009	52.75
2010	52.867
2011	52.993
2012	53.151
2013	53.306
2014	53.414
2015	53.466
2016	53.452
2017	53.374
2018	53.249
2019	53.107
2020	52.965
2021	52.818
2022	52.676
2023	52.52
2024	52.324
2025	52.075
2026	51.788
2027	51.461
2028	51.122
2029	50.812
2030	50.554