# year    value 
 1980 -0.945135 
 1981 -0.9238281 
 1982 -0.7922552 
 1983 -1.235064 
 1984 -0.9346909 
 1985 -0.9969018 
 1986 -0.8978382 
 1987 -0.9128545 
 1988 -0.7883805 
 1989 -0.6046931 
 1990 -0.6692882 
 1991 -0.6345482 
 1992 -1.088367 
 1993 -1.116345 
 1994 -0.8192272 
 1995 -0.7786388 
 1996 -0.6197057 
 1997 -0.6152357 
 1998 -0.5206833 
 1999 -0.6026214 
 2000 -0.2827254 
 2001 -0.3149144 
 2002 -0.4051069 
 2003 -0.3274007 
 2004 -0.2189822 
 2005 -0.3071326