Year Percent
1950 2.818
1951 2.93
1952 3.113
1953 3.223
1954 3.276
1955 3.287
1956 3.27
1957 3.234
1958 3.189
1959 3.138
1960 3.082
1961 3.015
1962 2.932
1963 2.829
1964 2.71
1965 2.588
1966 2.474
1967 2.374
1968 2.291
1969 2.227
1970 2.173
1971 2.126
1972 2.102
1973 2.117
1974 2.165
1975 2.228
1976 2.287
1977 2.336
1978 2.374
1979 2.4
1980 2.418
1981 2.43
1982 2.419
1983 2.371
1984 2.29
1985 2.189
1986 2.087
1987 1.996
1988 1.927
1989 1.878
1990 1.84
1991 1.801
1992 1.746
1993 1.669
1994 1.572
1995 1.466
1996 1.367
1997 1.285
1998 1.223
1999 1.183
2000 1.156
2001 1.136
2002 1.122
2003 1.117
2004 1.122
2005 1.13
2006 1.142
2007 1.165
2008 1.209
2009 1.27
2010 1.34
2011 1.406
2012 1.449
2013 1.455
2014 1.426
2015 1.378
2016 1.327
2017 1.28
2018 1.237
2019 1.2
2020 1.163
2021 1.124
2022 1.085
2023 1.046
2024 1.009
2025 0.972
2026 0.937
2027 0.902
2028 0.869
2029 0.838
2030 0.808
2031 0.778
2032 0.75
2033 0.722
2034 0.695
2035 0.669
2036 0.644
2037 0.619
2038 0.594
2039 0.57
2040 0.547
2041 0.524
2042 0.501
2043 0.479
2044 0.457
2045 0.434
2046 0.413
2047 0.391
2048 0.37
2049 0.35
2050 0.329
2051 0.309
2052 0.289
2053 0.269
2054 0.248
2055 0.227
2056 0.206
2057 0.186
2058 0.165
2059 0.145
2060 0.125
2061 0.105
2062 0.085
2063 0.066
2064 0.046
2065 0.027
2066 0.008
2067 -0.01
2068 -0.028
2069 -0.045
2070 -0.062
2071 -0.079
2072 -0.094
2073 -0.109
2074 -0.123
2075 -0.136
2076 -0.148
2077 -0.159
2078 -0.17
2079 -0.18
2080 -0.19
2081 -0.199
2082 -0.207
2083 -0.215
2084 -0.223
2085 -0.231
2086 -0.238
2087 -0.245
2088 -0.252
2089 -0.26
2090 -0.267
2091 -0.275
2092 -0.282
2093 -0.288
2094 -0.295
2095 -0.301
2096 -0.306
2097 -0.312
2098 -0.318
2099 -0.324