# year    value 
 1980     0.97 
 1981     2.35 
 1982    -0.91 
 1983     1.95 
 1984    -0.59 
 1985    -1.07 
 1986     0.92 
 1987     2.24 
 1988     0.12 
 1989    -0.09 
 1990     0.88 
 1991     0.48 
 1992      3.1 
 1993    -1.08 
 1994     -0.2 
 1995     2.03 
 1996     0.52 
 1997    -0.01 
 1998     2.28 
 1999     2.24 
 2000     2.96 
 2001    -0.72 
 2002      2.1 
 2003     1.35 
 2004     0.94 
 2005     1.98 
 2006     2.43 
 2007      0.5 
 2008     0.03 
 2009     0.46 
 2010    -1.01 
 2011    -0.28 
 2012     2.23 
 2013     1.06 
 2014    -0.61 
 2015     1.72 
 2016     2.85 
 2017     1.54 
 2018     0.45