Year Percent
1950 2.083
1951 2.169
1952 2.287
1953 2.354
1954 2.444
1955 2.602
1956 2.871
1957 3.286
1958 3.857
1959 4.555
1960 5.291
1961 5.949
1962 6.423
1963 6.64
1964 6.659
1965 6.642
1966 6.681
1967 6.692
1968 6.583
1969 6.405
1970 6.111
1971 5.78
1972 5.896
1973 6.763
1974 8.123
1975 9.589
1976 10.664
1977 10.723
1978 9.581
1979 7.654
1980 5.47
1981 3.537
1982 2.455
1983 2.622
1984 3.884
1985 5.625
1986 7.077
1987 7.605
1988 6.987
1989 5.491
1990 3.673
1991 2.046
1992 0.951
1993 0.591
1994 0.952
1995 1.684
1996 2.367
1997 2.789
1998 2.877
1999 2.645
2000 2.276
2001 1.957
2002 1.737
2003 1.617
2004 1.598
2005 1.625
2006 1.642
2007 1.651
2008 1.667
2009 1.685
2010 1.709
2011 1.734
2012 1.745
2013 1.728
2014 1.685
2015 1.627
2016 1.569
2017 1.519
2018 1.478
2019 1.445
2020 1.417
2021 1.387
2022 1.355
2023 1.321
2024 1.285
2025 1.249
2026 1.213
2027 1.177
2028 1.14
2029 1.102
2030 1.064
2031 1.026
2032 0.988
2033 0.951
2034 0.914
2035 0.877
2036 0.841
2037 0.806
2038 0.771
2039 0.738
2040 0.705
2041 0.673
2042 0.642
2043 0.611
2044 0.582
2045 0.554
2046 0.526
2047 0.499
2048 0.471
2049 0.445
2050 0.418
2051 0.392
2052 0.366
2053 0.34
2054 0.314
2055 0.289
2056 0.263
2057 0.238
2058 0.212
2059 0.186
2060 0.16
2061 0.135
2062 0.109
2063 0.085
2064 0.061
2065 0.037
2066 0.014
2067 -0.008
2068 -0.03
2069 -0.051
2070 -0.071
2071 -0.091
2072 -0.109
2073 -0.126
2074 -0.141
2075 -0.155
2076 -0.168
2077 -0.181
2078 -0.192
2079 -0.201
2080 -0.209
2081 -0.217
2082 -0.224
2083 -0.23
2084 -0.235
2085 -0.239
2086 -0.242
2087 -0.245
2088 -0.249
2089 -0.254
2090 -0.259
2091 -0.264
2092 -0.268
2093 -0.273
2094 -0.277
2095 -0.281
2096 -0.285
2097 -0.29
2098 -0.295
2099 -0.302