Year Percent
1950 1.747
1951 1.749
1952 1.754
1953 1.766
1954 1.783
1955 1.807
1956 1.84
1957 1.882
1958 1.931
1959 1.989
1960 2.051
1961 2.115
1962 2.176
1963 2.231
1964 2.28
1965 2.325
1966 2.372
1967 2.419
1968 2.464
1969 2.508
1970 2.551
1971 2.594
1972 2.638
1973 2.685
1974 2.734
1975 2.781
1976 2.826
1977 2.87
1978 2.916
1979 2.963
1980 3.005
1981 3.04
1982 3.067
1983 3.089
1984 3.104
1985 3.114
1986 3.116
1987 3.102
1988 3.064
1989 3.005
1990 2.939
1991 2.876
1992 2.814
1993 2.747
1994 2.678
1995 2.611
1996 2.55
1997 2.51
1998 2.501
1999 2.52
2000 2.553
2001 2.586
2002 2.616
2003 2.646
2004 2.673
2005 2.699
2006 2.722
2007 2.738
2008 2.742
2009 2.736
2010 2.724
2011 2.709
2012 2.692
2013 2.673
2014 2.65
2015 2.626
2016 2.601
2017 2.576
2018 2.551
2019 2.528
2020 2.506
2021 2.483
2022 2.46
2023 2.437
2024 2.415
2025 2.393
2026 2.371
2027 2.349
2028 2.328
2029 2.309
2030 2.289
2031 2.269
2032 2.249
2033 2.228
2034 2.206
2035 2.183
2036 2.161
2037 2.138
2038 2.115
2039 2.092
2040 2.068
2041 2.044
2042 2.02
2043 1.995
2044 1.969
2045 1.943
2046 1.917
2047 1.891
2048 1.866
2049 1.84
2050 1.815
2051 1.789
2052 1.763
2053 1.737
2054 1.711
2055 1.685
2056 1.659
2057 1.634
2058 1.608
2059 1.583
2060 1.559
2061 1.534
2062 1.51
2063 1.486
2064 1.463
2065 1.44
2066 1.418
2067 1.395
2068 1.372
2069 1.349
2070 1.326
2071 1.303
2072 1.28
2073 1.257
2074 1.234
2075 1.211
2076 1.189
2077 1.166
2078 1.144
2079 1.121
2080 1.099
2081 1.076
2082 1.054
2083 1.031
2084 1.009
2085 0.986
2086 0.964
2087 0.941
2088 0.919
2089 0.897
2090 0.875
2091 0.853
2092 0.832
2093 0.811
2094 0.79
2095 0.769
2096 0.749
2097 0.729
2098 0.709
2099 0.69