# year value 1940 -0.9471848 1941 -0.964034 1942 -1.036292 1943 -0.9759528 1944 -0.9959455 1945 -0.8782269 1946 -1.035837 1947 -0.9376785 1948 -0.887539 1949 -0.8924743 1950 -0.8910486 1951 -0.8828611 1952 -0.9176346 1953 -0.9391182 1954 -0.9872713 1955 -0.9794097 1956 -0.9284982 1957 -0.8981297 1958 -0.9539906 1959 -0.8924851 1960 -0.8665681 1961 -0.8722169 1962 -0.8730784 1963 -0.9527413 1964 -1.050206 1965 -1.11914 1966 -1.040477 1967 -0.9910187 1968 -1.046475 1969 -0.9396494 1970 -0.9485459 1971 -0.9028679 1972 -0.82223 1973 -0.8225108 1974 -0.7976024 1975 -0.8027449 1976 -0.8323708 1977 -0.7851667 1978 -0.6260691 1979 -0.5281922 1980 -0.5107787 1981 -0.4185696 1982 -0.6536686 1983 -0.8380732 1984 -0.680797 1985 -0.5516892 1986 -0.6024845 1987 -0.3324626 1988 -0.3172479 1989 -0.2991907 1990 -0.1104346 1991 -0.1876517 1992 -0.4121091 1993 -0.3558667 1994 -0.3198997 1995 -0.2744603 1996 -0.1370728 1997 0.03858766 1998 0.1319224 1999 0.2175708 2000 0.2927716 2001 0.4391905 2002 0.4461902 2003 0.5044477 2004 0.514851 2005 1.974341