# year    value 
 1980 0.1710949 
 1981 0.2385433 
 1982 -0.04413318 
 1983 -0.2758981 
 1984 0.07283679 
 1985 0.3560035 
 1986 0.401785 
 1987 0.4740825 
 1988 0.5844826 
 1989 0.4075772 
 1990 0.3122299 
 1991 0.1045254 
 1992 -0.2680719 
 1993 0.2564551 
 1994 0.5303617 
 1995 0.4628832 
 1996 0.3572873 
 1997 0.8028158 
 1998 0.7030505 
 1999 0.6946239 
 2000 0.9610432 
 2001 0.8212214 
 2002  1.00408 
 2003 0.9732178 
 2004 0.8791924 
 2005 0.7514011