# year    value 
 1980      0.3 
 1981     0.52 
 1982    -1.05 
 1983      0.5 
 1984    -0.99 
 1985    -2.13 
 1986     -0.8 
 1987      0.9 
 1988     0.93 
 1989     0.36 
 1990     0.98 
 1991     0.39 
 1992     0.13 
 1993    -0.68 
 1994    -0.53 
 1995      1.2 
 1996    -0.25 
 1997      0.6 
 1998     0.93 
 1999     1.29 
 2000    -0.97 
 2001     1.63 
 2002    -0.01 
 2003      0.9 
 2004    -0.01 
 2005     0.66 
 2006     0.02 
 2007     0.73 
 2008     1.08 
 2009     0.43 
 2010     0.61 
 2011     0.77 
 2012     1.55 
 2013      0.3 
 2014     1.47 
 2015      1.4 
 2016      1.7 
 2017     1.23 
 2018     0.39