# year    value 
 1980 -0.3286064 
 1981 -0.2167067 
 1982 -0.4639444 
 1983 -0.6759285 
 1984 -0.4496178 
 1985 -0.4095608 
 1986 -0.1871941 
 1987 -0.306738 
 1988 -0.1755217 
 1989 -0.1133147 
 1990 -0.1773223 
 1991 -0.08704196 
 1992 -0.6277745 
 1993 -0.4811592 
 1994 -0.03217315 
 1995 -0.2073758 
 1996 -0.07407499 
 1997 0.1460572 
 1998 0.2465748 
 1999 0.03958048 
 2000 0.3858355 
 2001 0.1885323 
 2002 0.2907951 
 2003 0.4036689 
 2004 0.3898628 
 2005 1.296646