# year    value 
 1980 1.214695 
 1981  1.27273 
 1982  1.31661 
 1983 0.8422704 
 1984 1.181337 
 1985 1.254849 
 1986 1.183045 
 1987 1.107033 
 1988 1.355817 
 1989 1.428387 
 1990 1.350529 
 1991 1.523002 
 1992 0.8219015 
 1993 0.9360302 
 1994 1.253633 
 1995 1.270122 
 1996 1.509204 
 1997 1.434868 
 1998 1.542659 
 1999 1.495013 
 2000 1.695858 
 2001 1.560632 
 2002  1.69313 
 2003 1.732467 
 2004 1.895747 
 2005 1.684853