Year Percent
1950 1.519
1951 1.508
1952 1.447
1953 1.341
1954 1.229
1955 1.13
1956 1.093
1957 1.156
1958 1.312
1959 1.572
1960 1.891
1961 2.197
1962 2.429
1963 2.519
1964 2.477
1965 2.357
1966 2.239
1967 2.184
1968 2.213
1969 2.323
1970 2.461
1971 2.57
1972 2.629
1973 2.624
1974 2.569
1975 2.488
1976 2.384
1977 2.255
1978 2.079
1979 1.856
1980 1.62
1981 1.394
1982 1.183
1983 0.938
1984 0.668
1985 0.391
1986 0.127
1987 -0.01
1988 0.093
1989 0.451
1990 0.957
1991 1.457
1992 1.795
1993 1.875
1994 1.717
1995 1.426
1996 1.132
1997 0.965
1998 1.004
1999 1.224
2000 1.547
2001 1.846
2002 1.985
2003 1.911
2004 1.623
2005 1.228
2006 0.859
2007 0.569
2008 0.415
2009 0.395
2010 0.437
2011 0.479
2012 0.504
2013 0.522
2014 0.524
2015 0.52
2016 0.528
2017 0.532
2018 0.507
2019 0.458
2020 0.397
2021 0.336
2022 0.283
2023 0.236
2024 0.207
2025 0.186
2026 0.155
2027 0.129
2028 0.109
2029 0.09
2030 0.078
2031 0.064
2032 0.052
2033 0.042
2034 0.029
2035 0.018
2036 0.009
2037 -0.001
2038 -0.018
2039 -0.034
2040 -0.047
2041 -0.063
2042 -0.081
2043 -0.105
2044 -0.128
2045 -0.155
2046 -0.186
2047 -0.21
2048 -0.232
2049 -0.259
2050 -0.286
2051 -0.308
2052 -0.332
2053 -0.351
2054 -0.368
2055 -0.387
2056 -0.398
2057 -0.408
2058 -0.422
2059 -0.426
2060 -0.427
2061 -0.429
2062 -0.427
2063 -0.425
2064 -0.422
2065 -0.419
2066 -0.413
2067 -0.404
2068 -0.398
2069 -0.391
2070 -0.381
2071 -0.374
2072 -0.37
2073 -0.365
2074 -0.362
2075 -0.352
2076 -0.344
2077 -0.342
2078 -0.337
2079 -0.332
2080 -0.335
2081 -0.331
2082 -0.329
2083 -0.33
2084 -0.326
2085 -0.333
2086 -0.33
2087 -0.327
2088 -0.334
2089 -0.336
2090 -0.342
2091 -0.351
2092 -0.351
2093 -0.355
2094 -0.364
2095 -0.377
2096 -0.387
2097 -0.389
2098 -0.397
2099 -0.415