Year	Percent
1950	2.997
1951	2.712
1952	2.268
1953	1.996
1954	1.832
1955	1.824
1956	1.947
1957	2.151
1958	2.428
1959	2.774
1960	3.156
1961	3.533
1962	3.84
1963	4.063
1964	4.191
1965	4.284
1966	4.369
1967	4.344
1968	4.19
1969	3.927
1970	3.631
1971	3.367
1972	3.172
1973	3.074
1974	3.065
1975	3.089
1976	3.144
1977	3.283
1978	3.553
1979	3.916
1980	4.282
1981	4.592
1982	4.896
1983	5.258
1984	5.631
1985	5.988
1986	6.265
1987	6.272
1988	5.906
1989	5.258
1990	4.514
1991	3.863
1992	3.396
1993	3.14
1994	3.091
1995	3.121
1996	3.129
1997	3.211
1998	3.454
1999	3.818
2000	4.237
2001	4.604
2002	4.756
2003	4.583
2004	4.143
2005	3.589
2006	3.082
2007	2.72
2008	2.551
2009	2.569
2010	2.671
2011	2.758
2012	2.798
2013	2.782
2014	2.712
2015	2.623
2016	2.547
2017	2.485
2018	2.436
2019	2.395
2020	2.361
2021	2.328
2022	2.294
2023	2.266
2024	2.239
2025	2.214
2026	2.19
2027	2.165
2028	2.142
2029	2.116
2030	2.089
2031	2.063
2032	2.037
2033	2.008
2034	1.979
2035	1.95
2036	1.918
2037	1.887
2038	1.854
2039	1.822
2040	1.787
2041	1.753
2042	1.72
2043	1.686
2044	1.653
2045	1.62
2046	1.588
2047	1.558
2048	1.527
2049	1.494
2050	1.464
2051	1.435
2052	1.406
2053	1.38
2054	1.355
2055	1.333
2056	1.309
2057	1.287
2058	1.267
2059	1.248
2060	1.228
2061	1.21
2062	1.192
2063	1.174
2064	1.156
2065	1.137
2066	1.119
2067	1.101
2068	1.083
2069	1.065
2070	1.046
2071	1.028
2072	1.01
2073	0.991
2074	0.972
2075	0.952
2076	0.934
2077	0.915
2078	0.895
2079	0.877
2080	0.858
2081	0.839
2082	0.82
2083	0.8
2084	0.781
2085	0.762
2086	0.742
2087	0.723
2088	0.704
2089	0.685
2090	0.668
2091	0.649
2092	0.631
2093	0.614
2094	0.598
2095	0.581
2096	0.565
2097	0.55
2098	0.535
2099	0.521