# year    value 
 1980 -1.372144 
 1981 -1.46331 
 1982 -1.50029 
 1983 -1.821962 
 1984 -1.487145 
 1985 -1.59923 
 1986 -1.438184 
 1987 -1.604771 
 1988 -1.552184 
 1989 -1.230793 
 1990 -1.314238 
 1991 -1.243766 
 1992 -1.590792 
 1993 -1.528323 
 1994 -1.097257 
 1995 -1.303146 
 1996 -1.361526 
 1997 -1.261746 
 1998 -1.056651 
 1999 -1.18422 
 2000 -0.7843969 
 2001 -0.8707947 
 2002 -1.079226 
 2003 -0.8034955 
 2004 -0.7847494 
 2005 -0.876884