# year    value 
 1980 0.2200996 
 1981 0.2863375 
 1982 -0.0180684 
 1983 -0.1614689 
 1984 0.1115897 
 1985 0.3445026 
 1986 0.3357113 
 1987 0.437246 
 1988 0.5222286 
 1989 0.5049768 
 1990 0.2807347 
 1991 0.193168 
 1992 -0.2660476 
 1993 0.2954403 
 1994 0.6023982 
 1995 0.4886902 
 1996 0.4031049 
 1997 0.8336032 
 1998 0.7173536 
 1999 0.7091701 
 2000 0.9766945 
 2001 0.8291877 
 2002 1.005229 
 2003 1.007557 
 2004 0.9670871 
 2005 0.8011082