Year	Percent
1990	52.998
1991	52.988
1992	52.979
1993	52.964
1994	52.983
1995	52.993
1996	52.995
1997	53.001
1998	53.013
1999	53.011
2000	53.017
2001	53.021
2002	53.026
2003	53.026
2004	53.028
2005	53.029
2006	53.029
2007	53.026
2008	53.025
2009	53.028
2010	53.027
2011	53.025
2012	53.022
2013	53.02
2014	53.016
2015	53.009
2016	53.005
2017	53.005
2018	53.006
2019	53.006
2020	53.006
2021	53.006
2022	53.007
2023	53.007
2024	53.007
2025	53.008
2026	53.008
2027	53.008
2028	53.008
2029	53.009
2030	53.009