Year Percent
1950 0.19
1951 0.357
1952 0.617
1953 0.746
1954 0.774
1955 0.73
1956 0.645
1957 0.546
1958 0.452
1959 0.377
1960 0.316
1961 0.251
1962 0.156
1963 0.007
1964 -0.185
1965 -0.411
1966 -0.632
1967 -0.726
1968 -0.586
1969 -0.213
1970 0.289
1971 0.786
1972 1.177
1973 1.403
1974 1.458
1975 1.426
1976 1.388
1977 1.324
1978 1.201
1979 1.027
1980 0.822
1981 0.613
1982 0.419
1983 0.258
1984 0.136
1985 0.03
1986 -0.072
1987 -0.133
1988 -0.114
1989 -0.017
1990 0.129
1991 0.282
1992 0.403
1993 0.467
1994 0.469
1995 0.438
1996 0.408
1997 0.39
1998 0.388
1999 0.402
2000 0.419
2001 0.426
2002 0.42
2003 0.403
2004 0.373
2005 0.339
2006 0.304
2007 0.245
2008 0.143
2009 0.001
2010 -0.166
2011 -0.332
2012 -0.462
2013 -0.526
2014 -0.521
2015 -0.478
2016 -0.429
2017 -0.389
2018 -0.364
2019 -0.355
2020 -0.352
2021 -0.345
2022 -0.336
2023 -0.331
2024 -0.331
2025 -0.333
2026 -0.337
2027 -0.341
2028 -0.345
2029 -0.349
2030 -0.353
2031 -0.358
2032 -0.365
2033 -0.372
2034 -0.381
2035 -0.39
2036 -0.4
2037 -0.412
2038 -0.425
2039 -0.439
2040 -0.455
2041 -0.472
2042 -0.488
2043 -0.506
2044 -0.523
2045 -0.541
2046 -0.558
2047 -0.576
2048 -0.595
2049 -0.614
2050 -0.633
2051 -0.651
2052 -0.668
2053 -0.683
2054 -0.697
2055 -0.708
2056 -0.719
2057 -0.728
2058 -0.736
2059 -0.742
2060 -0.746
2061 -0.749
2062 -0.75
2063 -0.749
2064 -0.747
2065 -0.742
2066 -0.737
2067 -0.73
2068 -0.721
2069 -0.71
2070 -0.699
2071 -0.686
2072 -0.673
2073 -0.658
2074 -0.642
2075 -0.626
2076 -0.61
2077 -0.594
2078 -0.58
2079 -0.567
2080 -0.556
2081 -0.545
2082 -0.535
2083 -0.528
2084 -0.522
2085 -0.519
2086 -0.515
2087 -0.513
2088 -0.512
2089 -0.511
2090 -0.511
2091 -0.512
2092 -0.511
2093 -0.511
2094 -0.509
2095 -0.506
2096 -0.502
2097 -0.497
2098 -0.491
2099 -0.482