Year Percent
1950 1.834
1951 1.86
1952 1.897
1953 1.904
1954 1.885
1955 1.842
1956 1.781
1957 1.703
1958 1.611
1959 1.509
1960 1.4
1961 1.291
1962 1.186
1963 1.091
1964 1.006
1965 0.927
1966 0.855
1967 0.797
1968 0.764
1969 0.756
1970 0.761
1971 0.772
1972 0.786
1973 0.806
1974 0.83
1975 0.854
1976 0.876
1977 0.896
1978 0.914
1979 0.928
1980 0.941
1981 0.95
1982 0.935
1983 0.879
1984 0.784
1985 0.668
1986 0.549
1987 0.45
1988 0.382
1989 0.347
1990 0.33
1991 0.312
1992 0.286
1993 0.25
1994 0.205
1995 0.156
1996 0.112
1997 0.071
1998 0.03
1999 -0.01
2000 -0.049
2001 -0.086
2002 -0.111
2003 -0.115
2004 -0.099
2005 -0.072
2006 -0.043
2007 -0.02
2008 -0.006
2009 -0.003
2010 -0.005
2011 -0.008
2012 -0.015
2013 -0.032
2014 -0.058
2015 -0.09
2016 -0.124
2017 -0.157
2018 -0.187
2019 -0.214
2020 -0.239
2021 -0.266
2022 -0.292
2023 -0.316
2024 -0.338
2025 -0.358
2026 -0.379
2027 -0.399
2028 -0.42
2029 -0.441
2030 -0.462
2031 -0.483
2032 -0.503
2033 -0.521
2034 -0.538
2035 -0.554
2036 -0.569
2037 -0.583
2038 -0.597
2039 -0.61
2040 -0.623
2041 -0.635
2042 -0.646
2043 -0.657
2044 -0.667
2045 -0.677
2046 -0.687
2047 -0.696
2048 -0.705
2049 -0.714
2050 -0.723
2051 -0.732
2052 -0.741
2053 -0.75
2054 -0.76
2055 -0.77
2056 -0.781
2057 -0.792
2058 -0.805
2059 -0.82
2060 -0.836
2061 -0.852
2062 -0.869
2063 -0.885
2064 -0.901
2065 -0.917
2066 -0.933
2067 -0.947
2068 -0.96
2069 -0.971
2070 -0.981
2071 -0.989
2072 -0.994
2073 -0.997
2074 -0.996
2075 -0.992
2076 -0.987
2077 -0.979
2078 -0.969
2079 -0.957
2080 -0.942
2081 -0.927
2082 -0.909
2083 -0.891
2084 -0.872
2085 -0.853
2086 -0.833
2087 -0.813
2088 -0.794
2089 -0.777
2090 -0.76
2091 -0.744
2092 -0.729
2093 -0.715
2094 -0.701
2095 -0.689
2096 -0.679
2097 -0.671
2098 -0.665
2099 -0.663