# year    value 
 1900 9.587987 
 1901 9.557706 
 1902 9.521851 
 1903 9.075211 
 1904 9.251234 
 1905 9.415187 
 1906 9.438517 
 1907 9.415072 
 1908 9.465073 
 1909 9.486167 
 1910 9.495642 
 1911 9.513199 
 1912 9.445111 
 1913 9.313054 
 1914 9.474982 
 1915 9.599854 
 1916 9.681697 
 1917 9.676412 
 1918 9.662933 
 1919 9.646106 
 1920 9.662733 
 1921 9.653235 
 1922  9.72995 
 1923 9.656683 
 1924 9.665225 
 1925 9.686316 
 1926 9.694911 
 1927 9.727401 
 1928 9.732598 
 1929  9.64033 
 1930 9.636501 
 1931 9.634085 
 1932 9.664096 
 1933 9.576086 
 1934 9.624095 
 1935 9.664273 
 1936 9.763132 
 1937 9.698511 
 1938 9.767432 
 1939 9.698391 
 1940 9.726326 
 1941 9.659621 
 1942 9.723056 
 1943 9.700351 
 1944 9.722086 
 1945 9.731281 
 1946 9.717299 
 1947 9.764885 
 1948 9.759172 
 1949 9.818672 
 1950 9.785394 
 1951 9.730658 
 1952 9.729403 
 1953 9.722335 
 1954 9.748334 
 1955 9.750546 
 1956 9.699233 
 1957 9.684512 
 1958   9.7276 
 1959 9.726505 
 1960 9.770255 
 1961  9.65252 
 1962 9.617439 
 1963 9.571212 
 1964 9.410694 
 1965 9.452297 
 1966 9.540067 
 1967 9.525608 
 1968 9.510726 
 1969 9.488974 
 1970 9.652748 
 1971 9.689275 
 1972 9.743498 
 1973 9.710023 
 1974 9.764857 
 1975 9.710151 
 1976 9.714964 
 1977 9.788561 
 1978 9.826633 
 1979 9.820318 
 1980 9.933713 
 1981 9.982495 
 1982 9.785229 
 1983 9.590977 
 1984 9.753532 
 1985 9.811719 
 1986 9.816764 
 1987  9.90816 
 1988  10.0104 
 1989  10.0767 
 1990 10.12259 
 1991 10.09165 
 1992 9.601318 
 1993 9.827022 
 1994 9.879515 
 1995 10.00149 
 1996 10.09357 
 1997 10.19179 
 1998 10.29467 
 1999 10.27706 
 2000  10.3132 
 2001  10.4101 
 2002 10.43699 
 2003 10.41503 
 2004 10.41467 
 2005 10.49995