# year value 1900 11.20518 1901 11.21988 1902 11.11187 1903 10.6515 1904 10.81627 1905 11.0598 1906 11.09961 1907 11.01738 1908 11.10187 1909 11.09792 1910 11.09475 1911 11.09358 1912 10.91057 1913 10.83785 1914 11.00257 1915 11.15007 1916 11.16602 1917 11.22863 1918 11.3204 1919 11.25181 1920 11.19767 1921 11.243 1922 11.29057 1923 11.27261 1924 11.24771 1925 11.27175 1926 11.29415 1927 11.33072 1928 11.35306 1929 11.22524 1930 11.21 1931 11.24116 1932 11.31623 1933 11.23673 1934 11.23 1935 11.23317 1936 11.32675 1937 11.36929 1938 11.36178 1939 11.32244 1940 11.35704 1941 11.31604 1942 11.29948 1943 11.24562 1944 11.3293 1945 11.31492 1946 11.31992 1947 11.33871 1948 11.28849 1949 11.43586 1950 11.35844 1951 11.35155 1952 11.33524 1953 11.31683 1954 11.25094 1955 11.32411 1956 11.31812 1957 11.29628 1958 11.29108 1959 11.28352 1960 11.38149 1961 11.26922 1962 11.21402 1963 11.1411 1964 11.00147 1965 11.0428 1966 11.08941 1967 11.14497 1968 11.04553 1969 10.99889 1970 11.13815 1971 11.1824 1972 11.2517 1973 11.24196 1974 11.27714 1975 11.1676 1976 11.28215 1977 11.32186 1978 11.39095 1979 11.41413 1980 11.48286 1981 11.57913 1982 11.34388 1983 11.06459 1984 11.39877 1985 11.50267 1986 11.51681 1987 11.55372 1988 11.61942 1989 11.73833 1990 11.67509 1991 11.75393 1992 11.1257 1993 11.38614 1994 11.68919 1995 11.72624 1996 11.76196 1997 11.9147 1998 12.00231 1999 11.95662 2000 12.11642 2001 12.13647 2002 12.14013 2003 12.19178 2004 12.18132 2005 12.20191