Year Percent
1950 0.722
1951 0.81
1952 0.979
1953 1.134
1954 1.274
1955 1.399
1956 1.512
1957 1.612
1958 1.699
1959 1.776
1960 1.844
1961 1.905
1962 1.961
1963 2.014
1964 2.066
1965 2.115
1966 2.161
1967 2.205
1968 2.247
1969 2.288
1970 2.329
1971 2.37
1972 2.411
1973 2.453
1974 2.495
1975 2.518
1976 2.519
1977 2.553
1978 2.665
1979 2.835
1980 3.02
1981 3.155
1982 3.16
1983 2.981
1984 2.636
1985 2.26
1986 1.94
1987 1.554
1988 0.974
1989 0.237
1990 -0.628
1991 -1.484
1992 -1.916
1993 -1.524
1994 -0.287
1995 1.446
1996 3.145
1997 4.355
1998 4.847
1999 4.696
2000 4.252
2001 3.852
2002 3.643
2003 3.665
2004 3.892
2005 4.189
2006 4.411
2007 4.487
2008 4.396
2009 4.162
2010 3.87
2011 3.598
2012 3.37
2013 3.19
2014 3.057
2015 2.946
2016 2.837
2017 2.738
2018 2.661
2019 2.605
2020 2.562
2021 2.523
2022 2.486
2023 2.447
2024 2.407
2025 2.367
2026 2.331
2027 2.297
2028 2.263
2029 2.228
2030 2.195
2031 2.162
2032 2.132
2033 2.103
2034 2.077
2035 2.052
2036 2.027
2037 2.002
2038 1.977
2039 1.952
2040 1.926
2041 1.9
2042 1.875
2043 1.85
2044 1.825
2045 1.799
2046 1.774
2047 1.749
2048 1.724
2049 1.698
2050 1.672
2051 1.647
2052 1.621
2053 1.594
2054 1.567
2055 1.54
2056 1.513
2057 1.486
2058 1.46
2059 1.433
2060 1.406
2061 1.38
2062 1.353
2063 1.327
2064 1.3
2065 1.274
2066 1.248
2067 1.222
2068 1.197
2069 1.172
2070 1.147
2071 1.122
2072 1.097
2073 1.073
2074 1.049
2075 1.025
2076 1.002
2077 0.978
2078 0.955
2079 0.932
2080 0.909
2081 0.886
2082 0.863
2083 0.841
2084 0.818
2085 0.796
2086 0.774
2087 0.752
2088 0.73
2089 0.709
2090 0.688
2091 0.668
2092 0.648
2093 0.628
2094 0.609
2095 0.59
2096 0.572
2097 0.554
2098 0.536
2099 0.52