Year Percent
1950 1.61
1951 1.603
1952 1.593
1953 1.588
1954 1.588
1955 1.593
1956 1.603
1957 1.617
1958 1.635
1959 1.657
1960 1.681
1961 1.707
1962 1.733
1963 1.758
1964 1.782
1965 1.818
1966 1.869
1967 1.901
1968 1.884
1969 1.828
1970 1.752
1971 1.694
1972 1.738
1973 1.946
1974 2.301
1975 2.726
1976 3.129
1977 3.446
1978 3.643
1979 3.73
1980 3.77
1981 3.817
1982 3.861
1983 3.882
1984 3.888
1985 3.862
1986 3.814
1987 3.849
1988 4.041
1989 4.354
1990 4.71
1991 5.002
1992 5.086
1993 4.883
1994 4.446
1995 3.915
1996 3.431
1997 3.072
1998 2.869
1999 2.815
2000 2.83
2001 2.839
2002 2.833
2003 2.82
2004 2.8
2005 2.778
2006 2.761
2007 2.749
2008 2.736
2009 2.721
2010 2.705
2011 2.687
2012 2.658
2013 2.613
2014 2.553
2015 2.486
2016 2.419
2017 2.356
2018 2.299
2019 2.249
2020 2.2
2021 2.152
2022 2.104
2023 2.056
2024 2.009
2025 1.963
2026 1.918
2027 1.873
2028 1.829
2029 1.785
2030 1.741
2031 1.699
2032 1.658
2033 1.619
2034 1.583
2035 1.549
2036 1.514
2037 1.479
2038 1.442
2039 1.403
2040 1.363
2041 1.323
2042 1.283
2043 1.244
2044 1.206
2045 1.167
2046 1.128
2047 1.089
2048 1.049
2049 1.008
2050 0.967
2051 0.926
2052 0.885
2053 0.844
2054 0.804
2055 0.764
2056 0.725
2057 0.686
2058 0.648
2059 0.611
2060 0.574
2061 0.538
2062 0.502
2063 0.468
2064 0.436
2065 0.404
2066 0.373
2067 0.343
2068 0.314
2069 0.286
2070 0.259
2071 0.232
2072 0.207
2073 0.183
2074 0.16
2075 0.137
2076 0.116
2077 0.095
2078 0.074
2079 0.053
2080 0.033
2081 0.013
2082 -0.006
2083 -0.025
2084 -0.044
2085 -0.063
2086 -0.08
2087 -0.098
2088 -0.115
2089 -0.132
2090 -0.149
2091 -0.165
2092 -0.181
2093 -0.196
2094 -0.211
2095 -0.226
2096 -0.24
2097 -0.254
2098 -0.268
2099 -0.281