# year value 1900 -0.6070495 1901 -0.6683109 1902 -0.6690583 1903 -0.9665721 1904 -0.8792382 1905 -0.7779075 1906 -0.7197768 1907 -0.6703159 1908 -0.6894762 1909 -0.6462321 1910 -0.6340215 1911 -0.5823128 1912 -0.6070997 1913 -0.7301014 1914 -0.6615431 1915 -0.6159943 1916 -0.5035073 1917 -0.5346368 1918 -0.5533584 1919 -0.5361669 1920 -0.4999941 1921 -0.5439837 1922 -0.4840916 1923 -0.4829604 1924 -0.4794901 1925 -0.465168 1926 -0.4605724 1927 -0.456375 1928 -0.4881935 1929 -0.5247537 1930 -0.5328564 1931 -0.4956186 1932 -0.5075042 1933 -0.498151 1934 -0.5363861 1935 -0.4298948 1936 -0.3910307 1937 -0.4591797 1938 -0.4050912 1939 -0.4039514 1940 -0.4847424 1941 -0.4779731 1942 -0.4142783 1943 -0.3864983 1944 -0.3756109 1945 -0.4202592 1946 -0.4325738 1947 -0.3866207 1948 -0.3741764 1949 -0.3667419 1950 -0.3851348 1951 -0.4120134 1952 -0.4115068 1953 -0.3860659 1954 -0.4032971 1955 -0.4106394 1956 -0.3914212 1957 -0.3989964 1958 -0.3816758 1959 -0.3949537 1960 -0.4031738 1961 -0.4216551 1962 -0.4259283 1963 -0.5312101 1964 -0.6617498 1965 -0.6343118 1966 -0.5746596 1967 -0.5359904 1968 -0.5890658 1969 -0.5673246 1970 -0.4998911 1971 -0.4013587 1972 -0.3741577 1973 -0.3425083 1974 -0.3942222 1975 -0.3832868 1976 -0.3528671 1977 -0.3442781 1978 -0.3234954 1979 -0.2585793 1980 -0.1890031 1981 -0.1681406 1982 -0.3677922 1983 -0.4590566 1984 -0.3158014 1985 -0.2843809 1986 -0.2610683 1987 -0.1795381 1988 -0.100799 1989 -0.06778826 1990 -0.02542231 1991 -0.1226023 1992 -0.4580822 1993 -0.2795064 1994 -0.2100029 1995 -0.107416 1996 -0.001503574 1997 0.06919787 1998 0.1070491 1999 0.1209353 2000 0.1624775 2001 0.228432 2002 0.2818628 2003 0.2521245 2004 0.2450613 2005 0.8637112