Year Percent
1950 2.799
1951 2.871
1952 3.006
1953 3.121
1954 3.209
1955 3.269
1956 3.297
1957 3.294
1958 3.261
1959 3.202
1960 3.129
1961 3.056
1962 3
1963 2.972
1964 2.972
1965 2.984
1966 2.993
1967 3.003
1968 3.018
1969 3.037
1970 3.054
1971 3.066
1972 3.075
1973 3.081
1974 3.083
1975 3.08
1976 3.069
1977 3.043
1978 2.995
1979 2.927
1980 2.852
1981 2.777
1982 2.697
1983 2.605
1984 2.504
1985 2.396
1986 2.29
1987 2.209
1988 2.171
1989 2.171
1990 2.19
1991 2.203
1992 2.191
1993 2.14
1994 2.054
1995 1.953
1996 1.856
1997 1.764
1998 1.675
1999 1.588
2000 1.503
2001 1.421
2002 1.355
2003 1.316
2004 1.304
2005 1.306
2006 1.31
2007 1.307
2008 1.291
2009 1.264
2010 1.231
2011 1.2
2012 1.174
2013 1.151
2014 1.133
2015 1.118
2016 1.102
2017 1.084
2018 1.063
2019 1.038
2020 1.01
2021 0.983
2022 0.961
2023 0.947
2024 0.942
2025 0.941
2026 0.939
2027 0.93
2028 0.91
2029 0.879
2030 0.842
2031 0.805
2032 0.771
2033 0.74
2034 0.712
2035 0.686
2036 0.66
2037 0.633
2038 0.606
2039 0.579
2040 0.553
2041 0.527
2042 0.501
2043 0.475
2044 0.449
2045 0.423
2046 0.398
2047 0.372
2048 0.348
2049 0.325
2050 0.301
2051 0.278
2052 0.255
2053 0.232
2054 0.208
2055 0.184
2056 0.16
2057 0.137
2058 0.113
2059 0.089
2060 0.065
2061 0.041
2062 0.017
2063 -0.007
2064 -0.032
2065 -0.056
2066 -0.08
2067 -0.104
2068 -0.128
2069 -0.152
2070 -0.175
2071 -0.198
2072 -0.221
2073 -0.242
2074 -0.263
2075 -0.283
2076 -0.303
2077 -0.322
2078 -0.34
2079 -0.356
2080 -0.372
2081 -0.388
2082 -0.402
2083 -0.416
2084 -0.428
2085 -0.44
2086 -0.451
2087 -0.461
2088 -0.471
2089 -0.48
2090 -0.488
2091 -0.496
2092 -0.503
2093 -0.51
2094 -0.516
2095 -0.522
2096 -0.527
2097 -0.532
2098 -0.536
2099 -0.541