Year Percent
1950 0.535
1951 0.587
1952 0.654
1953 0.656
1954 0.619
1955 0.572
1956 0.538
1957 0.537
1958 0.589
1959 0.693
1960 0.829
1961 0.963
1962 1.041
1963 1.028
1964 0.923
1965 0.766
1966 0.612
1967 0.511
1968 0.497
1969 0.568
1970 0.685
1971 0.794
1972 0.861
1973 0.874
1974 0.827
1975 0.759
1976 0.699
1977 0.628
1978 0.529
1979 0.409
1980 0.274
1981 0.145
1982 0.072
1983 0.095
1984 0.216
1985 0.391
1986 0.568
1987 0.734
1988 0.885
1989 1.015
1990 1.132
1991 1.242
1992 1.335
1993 1.391
1994 1.409
1995 1.417
1996 1.428
1997 1.409
1998 1.326
1999 1.192
2000 1.025
2001 0.866
2002 0.803
2003 0.904
2004 1.162
2005 1.497
2006 1.81
2007 2.057
2008 2.22
2009 2.295
2010 2.329
2011 2.355
2012 2.328
2013 2.198
2014 1.981
2015 1.717
2016 1.453
2017 1.25
2018 1.147
2019 1.141
2020 1.187
2021 1.231
2022 1.248
2023 1.232
2024 1.18
2025 1.113
2026 1.053
2027 1.008
2028 0.98
2029 0.967
2030 0.963
2031 0.959
2032 0.951
2033 0.938
2034 0.921
2035 0.902
2036 0.884
2037 0.867
2038 0.851
2039 0.835
2040 0.818
2041 0.801
2042 0.786
2043 0.772
2044 0.76
2045 0.749
2046 0.739
2047 0.727
2048 0.714
2049 0.699
2050 0.682
2051 0.666
2052 0.652
2053 0.638
2054 0.625
2055 0.613
2056 0.601
2057 0.59
2058 0.58
2059 0.571
2060 0.563
2061 0.556
2062 0.549
2063 0.542
2064 0.536
2065 0.53
2066 0.524
2067 0.519
2068 0.511
2069 0.504
2070 0.498
2071 0.49
2072 0.482
2073 0.474
2074 0.465
2075 0.457
2076 0.448
2077 0.44
2078 0.433
2079 0.427
2080 0.421
2081 0.416
2082 0.411
2083 0.405
2084 0.4
2085 0.395
2086 0.389
2087 0.383
2088 0.378
2089 0.372
2090 0.365
2091 0.359
2092 0.352
2093 0.346
2094 0.34
2095 0.333
2096 0.326
2097 0.32
2098 0.312
2099 0.305