# year    value 
 1980 -0.3260167 
 1981 -0.2094216 
 1982 -0.4604367 
 1983 -0.686646 
 1984 -0.4454139 
 1985 -0.4389254 
 1986 -0.2212953 
 1987 -0.2791216 
 1988 -0.2348755 
 1989 -0.09603365 
 1990 -0.2101509 
 1991 -0.04664167 
 1992 -0.6564461 
 1993 -0.4783429 
 1994 0.01214596 
 1995 -0.1323392 
 1996 -0.0690964 
 1997 0.1448651 
 1998 0.237197 
 1999 0.06928998 
 2000 0.4037232 
 2001 0.1315369 
 2002 0.2720222 
 2003 0.3947392 
 2004 0.3791994 
 2005 1.328684