Year Percent
1950 1.081
1951 1.049
1952 0.994
1953 0.957
1954 0.931
1955 0.913
1956 0.897
1957 0.881
1958 0.861
1959 0.837
1960 0.81
1961 0.785
1962 0.769
1963 0.766
1964 0.776
1965 0.791
1966 0.804
1967 0.809
1968 0.804
1969 0.786
1970 0.762
1971 0.738
1972 0.706
1973 0.657
1974 0.593
1975 0.521
1976 0.451
1977 0.392
1978 0.352
1979 0.33
1980 0.319
1981 0.312
1982 0.311
1983 0.323
1984 0.345
1985 0.374
1986 0.406
1987 0.438
1988 0.465
1989 0.489
1990 0.51
1991 0.532
1992 0.551
1993 0.567
1994 0.578
1995 0.591
1996 0.606
1997 0.614
1998 0.604
1999 0.58
2000 0.546
2001 0.516
2002 0.516
2003 0.571
2004 0.677
2005 0.807
2006 0.933
2007 1.041
2008 1.126
2009 1.185
2010 1.232
2011 1.274
2012 1.292
2013 1.264
2014 1.194
2015 1.1
2016 1.005
2017 0.93
2018 0.892
2019 0.892
2020 0.91
2021 0.925
2022 0.932
2023 0.93
2024 0.918
2025 0.902
2026 0.887
2027 0.873
2028 0.856
2029 0.838
2030 0.819
2031 0.799
2032 0.78
2033 0.76
2034 0.741
2035 0.722
2036 0.703
2037 0.686
2038 0.67
2039 0.655
2040 0.642
2041 0.63
2042 0.618
2043 0.609
2044 0.602
2045 0.597
2046 0.592
2047 0.585
2048 0.577
2049 0.567
2050 0.556
2051 0.545
2052 0.534
2053 0.524
2054 0.513
2055 0.503
2056 0.493
2057 0.483
2058 0.473
2059 0.465
2060 0.456
2061 0.448
2062 0.44
2063 0.433
2064 0.427
2065 0.42
2066 0.414
2067 0.409
2068 0.403
2069 0.397
2070 0.392
2071 0.386
2072 0.38
2073 0.373
2074 0.365
2075 0.356
2076 0.347
2077 0.339
2078 0.33
2079 0.32
2080 0.311
2081 0.302
2082 0.293
2083 0.284
2084 0.277
2085 0.27
2086 0.263
2087 0.256
2088 0.25
2089 0.244
2090 0.239
2091 0.234
2092 0.228
2093 0.223
2094 0.217
2095 0.212
2096 0.205
2097 0.199
2098 0.193
2099 0.187