Year Percent
1950 4.515
1951 4.428
1952 4.255
1953 4.094
1954 3.953
1955 3.839
1956 3.758
1957 3.715
1958 3.709
1959 3.733
1960 3.771
1961 3.803
1962 3.803
1963 3.755
1964 3.665
1965 3.558
1966 3.457
1967 3.358
1968 3.252
1969 3.142
1970 3.032
1971 2.927
1972 2.846
1973 2.8
1974 2.786
1975 2.788
1976 2.79
1977 2.784
1978 2.767
1979 2.739
1980 2.705
1981 2.671
1982 2.643
1983 2.623
1984 2.611
1985 2.601
1986 2.587
1987 2.56
1988 2.513
1989 2.449
1990 2.376
1991 2.305
1992 2.239
1993 2.181
1994 2.13
1995 2.082
1996 2.035
1997 1.989
1998 1.949
1999 1.912
2000 1.878
2001 1.845
2002 1.811
2003 1.776
2004 1.739
2005 1.703
2006 1.667
2007 1.63
2008 1.591
2009 1.55
2010 1.509
2011 1.468
2012 1.43
2013 1.394
2014 1.362
2015 1.332
2016 1.302
2017 1.271
2018 1.24
2019 1.207
2020 1.174
2021 1.141
2022 1.109
2023 1.079
2024 1.051
2025 1.023
2026 0.996
2027 0.968
2028 0.939
2029 0.91
2030 0.88
2031 0.85
2032 0.822
2033 0.794
2034 0.766
2035 0.74
2036 0.713
2037 0.687
2038 0.662
2039 0.637
2040 0.612
2041 0.588
2042 0.564
2043 0.54
2044 0.516
2045 0.493
2046 0.47
2047 0.447
2048 0.426
2049 0.405
2050 0.385
2051 0.365
2052 0.346
2053 0.327
2054 0.308
2055 0.289
2056 0.271
2057 0.254
2058 0.237
2059 0.22
2060 0.204
2061 0.187
2062 0.172
2063 0.156
2064 0.141
2065 0.126
2066 0.111
2067 0.096
2068 0.081
2069 0.066
2070 0.051
2071 0.036
2072 0.021
2073 0.007
2074 -0.008
2075 -0.023
2076 -0.037
2077 -0.051
2078 -0.065
2079 -0.078
2080 -0.09
2081 -0.103
2082 -0.115
2083 -0.126
2084 -0.137
2085 -0.148
2086 -0.158
2087 -0.168
2088 -0.178
2089 -0.187
2090 -0.196
2091 -0.205
2092 -0.213
2093 -0.221
2094 -0.229
2095 -0.236
2096 -0.244
2097 -0.251
2098 -0.257
2099 -0.264