Year Percent
1950 1.818
1951 1.847
1952 1.903
1953 1.954
1954 2.001
1955 2.045
1956 2.085
1957 2.12
1958 2.153
1959 2.182
1960 2.211
1961 2.241
1962 2.273
1963 2.31
1964 2.353
1965 2.398
1966 2.444
1967 2.492
1968 2.544
1969 2.598
1970 2.652
1971 2.705
1972 2.759
1973 2.816
1974 2.876
1975 2.96
1976 3.066
1977 3.128
1978 3.09
1979 2.977
1980 2.772
1981 2.542
1982 2.57
1983 3.076
1984 3.965
1985 5.027
1986 5.936
1987 6.229
1988 5.667
1989 4.432
1990 2.918
1991 1.524
1992 0.591
1993 0.344
1994 0.779
1995 1.572
1996 2.33
1997 2.859
1998 3.093
1999 3.042
2000 2.866
2001 2.726
2002 2.667
2003 2.683
2004 2.771
2005 2.886
2006 2.982
2007 3.04
2008 3.06
2009 3.044
2010 3.01
2011 2.976
2012 2.949
2013 2.93
2014 2.919
2015 2.91
2016 2.898
2017 2.881
2018 2.861
2019 2.837
2020 2.811
2021 2.785
2022 2.761
2023 2.74
2024 2.723
2025 2.708
2026 2.69
2027 2.669
2028 2.643
2029 2.612
2030 2.578
2031 2.544
2032 2.511
2033 2.478
2034 2.446
2035 2.415
2036 2.382
2037 2.35
2038 2.318
2039 2.285
2040 2.253
2041 2.221
2042 2.189
2043 2.156
2044 2.123
2045 2.09
2046 2.057
2047 2.025
2048 1.993
2049 1.961
2050 1.93
2051 1.899
2052 1.868
2053 1.837
2054 1.805
2055 1.774
2056 1.742
2057 1.711
2058 1.679
2059 1.648
2060 1.617
2061 1.586
2062 1.555
2063 1.524
2064 1.493
2065 1.462
2066 1.432
2067 1.401
2068 1.37
2069 1.34
2070 1.309
2071 1.279
2072 1.25
2073 1.22
2074 1.191
2075 1.163
2076 1.134
2077 1.107
2078 1.079
2079 1.052
2080 1.026
2081 0.999
2082 0.973
2083 0.947
2084 0.921
2085 0.896
2086 0.87
2087 0.845
2088 0.821
2089 0.798
2090 0.775
2091 0.752
2092 0.729
2093 0.707
2094 0.685
2095 0.664
2096 0.642
2097 0.622
2098 0.601
2099 0.582