# year    value 
 1960 -0.550644 
 1961 -0.4602843 
 1962 -0.4977951 
 1963 -0.4944696 
 1964 -0.8443307 
 1965 -0.7494121 
 1966 -0.7861576 
 1967 -0.7432607 
 1968 -0.6453682 
 1969 -0.7264907 
 1970 -0.6051148 
 1971 -0.4944567 
 1972 -0.5642206 
 1973 -0.5449187 
 1974 -0.4936903 
 1975 -0.528886 
 1976 -0.4639456 
 1977 -0.4275927 
 1978 -0.3750011 
 1979 -0.2744016 
 1980 -0.3318376 
 1981 -0.2257966 
 1982 -0.4683207 
 1983 -0.6625561 
 1984 -0.4548633 
 1985 -0.3729226 
 1986 -0.1446456 
 1987 -0.3411952 
 1988 -0.1014651 
 1989 -0.1348764 
 1990 -0.1363615 
 1991 -0.13745 
 1992 -0.5920005 
 1993 -0.4846727 
 1994 -0.08747063 
 1995 -0.3009997 
 1996 -0.08028663 
 1997 0.1475447 
 1998 0.2582757 
 1999 0.002511452 
 2000 0.3635166 
 2001 0.2596461 
 2002 0.3142184 
 2003 0.4148105 
 2004 0.4031678 
 2005 1.256673