# year value 1900 -1.097079 1901 -1.324035 1902 -1.235768 1903 -1.750065 1904 -1.870425 1905 -1.54142 1906 -1.382758 1907 -1.568104 1908 -1.612614 1909 -1.493538 1910 -1.404768 1911 -1.388327 1912 -1.929663 1913 -1.791953 1914 -1.621021 1915 -1.410059 1916 -1.592099 1917 -1.382509 1918 -1.194807 1919 -1.181319 1920 -1.224891 1921 -1.134393 1922 -1.159171 1923 -0.9209732 1924 -1.171537 1925 -1.206879 1926 -1.14876 1927 -0.9282391 1928 -1.069924 1929 -1.031364 1930 -1.17431 1931 -1.083965 1932 -1.274813 1933 -1.313414 1934 -1.169555 1935 -1.274604 1936 -1.311215 1937 -1.132946 1938 -1.030292 1939 -1.11447 1940 -1.230228 1941 -0.8413469 1942 -1.049519 1943 -1.027386 1944 -1.168749 1945 -0.8926877 1946 -1.084599 1947 -1.172298 1948 -1.021072 1949 -0.8786706 1950 -0.9464204 1951 -0.941722 1952 -1.090421 1953 -1.092482 1954 -1.039229 1955 -1.045245 1956 -1.03184 1957 -0.9004955 1958 -1.266808 1959 -0.8235633 1960 -1.041937 1961 -0.8717285 1962 -0.8815938 1963 -1.004292 1964 -1.021001 1965 -1.244178 1966 -1.258796 1967 -1.086991 1968 -1.068166 1969 -0.8940593 1970 -1.038121 1971 -0.8540061 1972 -1.141861 1973 -0.7909954 1974 -0.9533332 1975 -0.8095654 1976 -0.8349952 1977 -0.9289629 1978 -0.5020068 1979 -0.5831333 1980 -0.6872467 1981 -0.4637714 1982 -0.736579 1983 -0.947096 1984 -0.9046923 1985 -0.8173648 1986 -0.7006372 1987 -0.4308413 1988 -0.2421873 1989 -0.394726 1990 -0.006756082 1991 -0.2411925 1992 -0.6778738 1993 -0.4279923 1994 -0.4416344 1995 -0.1687204 1996 -0.005303209 1997 -0.08206979 1998 0.2890303 1999 0.2033305 2000 0.3207756 2001 0.2852446 2002 0.4912892 2003 0.4523959 2004 0.513916 2005 0.4741522