# year value 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