Year Percent
1950 1.107
1951 1.089
1952 1.051
1953 1.011
1954 0.972
1955 0.944
1956 0.931
1957 0.938
1958 0.968
1959 1.02
1960 1.084
1961 1.148
1962 1.193
1963 1.205
1964 1.183
1965 1.145
1966 1.106
1967 1.069
1968 1.034
1969 1.003
1970 0.974
1971 0.942
1972 0.908
1973 0.872
1974 0.836
1975 0.799
1976 0.762
1977 0.731
1978 0.706
1979 0.688
1980 0.66
1981 0.614
1982 0.588
1983 0.618
1984 0.694
1985 0.815
1986 0.937
1987 0.908
1988 0.601
1989 0.034
1990 -0.698
1991 -1.44
1992 -1.982
1993 -2.14
1994 -1.884
1995 -1.369
1996 -0.821
1997 -0.403
1998 -0.209
1999 -0.258
2000 -0.431
2001 -0.589
2002 -0.681
2003 -0.698
2004 -0.633
2005 -0.526
2006 -0.429
2007 -0.356
2008 -0.308
2009 -0.285
2010 -0.277
2011 -0.27
2012 -0.26
2013 -0.249
2014 -0.237
2015 -0.225
2016 -0.217
2017 -0.216
2018 -0.223
2019 -0.239
2020 -0.26
2021 -0.282
2022 -0.305
2023 -0.329
2024 -0.35
2025 -0.372
2026 -0.394
2027 -0.414
2028 -0.43
2029 -0.442
2030 -0.45
2031 -0.458
2032 -0.463
2033 -0.465
2034 -0.463
2035 -0.458
2036 -0.453
2037 -0.448
2038 -0.444
2039 -0.441
2040 -0.439
2041 -0.436
2042 -0.435
2043 -0.438
2044 -0.443
2045 -0.45
2046 -0.457
2047 -0.465
2048 -0.474
2049 -0.483
2050 -0.493
2051 -0.503
2052 -0.513
2053 -0.524
2054 -0.534
2055 -0.543
2056 -0.553
2057 -0.562
2058 -0.571
2059 -0.579
2060 -0.587
2061 -0.594
2062 -0.599
2063 -0.603
2064 -0.606
2065 -0.607
2066 -0.607
2067 -0.606
2068 -0.604
2069 -0.6
2070 -0.595
2071 -0.59
2072 -0.584
2073 -0.576
2074 -0.567
2075 -0.558
2076 -0.547
2077 -0.536
2078 -0.525
2079 -0.514
2080 -0.501
2081 -0.489
2082 -0.477
2083 -0.464
2084 -0.45
2085 -0.437
2086 -0.425
2087 -0.413
2088 -0.403
2089 -0.392
2090 -0.383
2091 -0.377
2092 -0.37
2093 -0.365
2094 -0.363
2095 -0.362
2096 -0.363
2097 -0.367
2098 -0.373
2099 -0.382