# year    value 
 1980 -1.277965 
 1981  -1.1704 
 1982 -1.177918 
 1983 -1.567942 
 1984 -1.304883 
 1985 -1.384165 
 1986 -1.29861 
 1987 -1.199664 
 1988 -1.164552 
 1989 -0.9626743 
 1990 -0.9291152 
 1991 -0.9586719 
 1992 -1.407749 
 1993 -1.299425 
 1994 -1.109016 
 1995 -1.05466 
 1996 -1.025927 
 1997 -0.8734968 
 1998 -0.8482232 
 1999 -0.8423563 
 2000 -0.7131856 
 2001 -0.6199116 
 2002 -0.7554455 
 2003 -0.6464928 
 2004 -0.5893896 
 2005 -0.5523372