Year Percent
1950 2.511
1951 2.528
1952 2.559
1953 2.584
1954 2.607
1955 2.63
1956 2.656
1957 2.687
1958 2.724
1959 2.766
1960 2.808
1961 2.845
1962 2.869
1963 2.875
1964 2.864
1965 2.844
1966 2.824
1967 2.801
1968 2.773
1969 2.741
1970 2.706
1971 2.669
1972 2.641
1973 2.631
1974 2.637
1975 2.649
1976 2.658
1977 2.65
1978 2.618
1979 2.565
1980 2.5
1981 2.436
1982 2.381
1983 2.342
1984 2.316
1985 2.294
1986 2.267
1987 2.234
1988 2.193
1989 2.145
1990 2.095
1991 2.043
1992 1.982
1993 1.904
1994 1.81
1995 1.71
1996 1.614
1997 1.528
1998 1.457
1999 1.399
2000 1.351
2001 1.307
2002 1.271
2003 1.247
2004 1.233
2005 1.226
2006 1.221
2007 1.223
2008 1.237
2009 1.261
2010 1.291
2011 1.319
2012 1.336
2013 1.332
2014 1.309
2015 1.276
2016 1.241
2017 1.209
2018 1.18
2019 1.154
2020 1.13
2021 1.103
2022 1.076
2023 1.049
2024 1.023
2025 0.998
2026 0.973
2027 0.946
2028 0.919
2029 0.891
2030 0.863
2031 0.834
2032 0.807
2033 0.781
2034 0.756
2035 0.731
2036 0.707
2037 0.683
2038 0.659
2039 0.636
2040 0.612
2041 0.589
2042 0.566
2043 0.543
2044 0.519
2045 0.496
2046 0.472
2047 0.449
2048 0.426
2049 0.403
2050 0.38
2051 0.358
2052 0.335
2053 0.314
2054 0.292
2055 0.272
2056 0.251
2057 0.231
2058 0.211
2059 0.191
2060 0.172
2061 0.153
2062 0.134
2063 0.116
2064 0.098
2065 0.081
2066 0.063
2067 0.047
2068 0.03
2069 0.014
2070 -0.002
2071 -0.018
2072 -0.033
2073 -0.048
2074 -0.063
2075 -0.078
2076 -0.093
2077 -0.107
2078 -0.12
2079 -0.133
2080 -0.144
2081 -0.156
2082 -0.167
2083 -0.178
2084 -0.189
2085 -0.2
2086 -0.211
2087 -0.221
2088 -0.23
2089 -0.238
2090 -0.246
2091 -0.253
2092 -0.261
2093 -0.268
2094 -0.276
2095 -0.283
2096 -0.291
2097 -0.298
2098 -0.305
2099 -0.311