Year Percent
1950 1.811
1951 1.696
1952 1.492
1953 1.337
1954 1.222
1955 1.137
1956 1.076
1957 1.03
1958 0.995
1959 0.968
1960 0.949
1961 0.944
1962 0.958
1963 0.996
1964 1.056
1965 1.125
1966 1.191
1967 1.252
1968 1.308
1969 1.355
1970 1.397
1971 1.433
1972 1.439
1973 1.394
1974 1.302
1975 1.184
1976 1.063
1977 0.958
1978 0.88
1979 0.829
1980 0.792
1981 0.753
1982 0.709
1983 0.658
1984 0.601
1985 0.542
1986 0.485
1987 0.437
1988 0.399
1989 0.371
1990 0.35
1991 0.331
1992 0.31
1993 0.287
1994 0.261
1995 0.234
1996 0.208
1997 0.186
1998 0.17
1999 0.16
2000 0.152
2001 0.144
2002 0.135
2003 0.121
2004 0.105
2005 0.085
2006 0.066
2007 0.046
2008 0.024
2009 0.001
2010 -0.024
2011 -0.049
2012 -0.075
2013 -0.103
2014 -0.132
2015 -0.162
2016 -0.192
2017 -0.221
2018 -0.248
2019 -0.272
2020 -0.295
2021 -0.317
2022 -0.338
2023 -0.36
2024 -0.38
2025 -0.4
2026 -0.419
2027 -0.437
2028 -0.453
2029 -0.468
2030 -0.482
2031 -0.495
2032 -0.508
2033 -0.52
2034 -0.531
2035 -0.542
2036 -0.552
2037 -0.561
2038 -0.567
2039 -0.572
2040 -0.576
2041 -0.579
2042 -0.581
2043 -0.58
2044 -0.579
2045 -0.576
2046 -0.572
2047 -0.569
2048 -0.565
2049 -0.562
2050 -0.559
2051 -0.556
2052 -0.554
2053 -0.556
2054 -0.56
2055 -0.567
2056 -0.574
2057 -0.581
2058 -0.59
2059 -0.6
2060 -0.611
2061 -0.622
2062 -0.631
2063 -0.639
2064 -0.644
2065 -0.648
2066 -0.65
2067 -0.651
2068 -0.649
2069 -0.645
2070 -0.638
2071 -0.63
2072 -0.619
2073 -0.605
2074 -0.587
2075 -0.566
2076 -0.544
2077 -0.523
2078 -0.504
2079 -0.488
2080 -0.473
2081 -0.459
2082 -0.444
2083 -0.431
2084 -0.418
2085 -0.406
2086 -0.395
2087 -0.385
2088 -0.376
2089 -0.368
2090 -0.362
2091 -0.356
2092 -0.35
2093 -0.345
2094 -0.341
2095 -0.337
2096 -0.333
2097 -0.33
2098 -0.327
2099 -0.325