Year	Percent
1961	1.11955
1962	1.14163
1963	1.15047
1964	1.2145
1965	1.2145
1966	1.20788
1967	1.25425
1968	1.29621
1969	1.34037
1970	1.37791
1971	1.43091
1972	1.45299
1973	1.49494
1974	1.55456
1975	1.60314
1976	1.6451
1977	1.67381
1978	1.72901
1979	1.75109
1980	1.75993
1981	1.77317
1982	1.75551
1983	1.74888
1984	1.78201
1985	1.82838
1986	1.89021
1987	1.90346
1988	1.95866
1989	2.00062
1990	2.0492
1991	2.06024
1992	2.08011
1993	2.14415
1994	2.15961
1995	2.19494
1996	2.24352
1997	2.25898
1998	2.34951
1999	2.38705
2000	2.40251
2001	2.41355
2002	2.43563
2003	2.44667
2004	2.4798
2005	2.50188
2006	2.54162
2007	2.67632
2008	2.74919
2009	2.79777
2010	2.79777
2011	2.83973
2012	2.83973
2013	2.83973
2014	2.88169
2015	2.91922
2016	2.93247
2017	3.1025
2018	3.1025
2019	3.1003
2020	3.13121
2021	3.182