# year    value 
 1980     0.37 
 1981     0.99 
 1982    -1.06 
 1983     0.11 
 1984    -0.06 
 1985    -0.01 
 1986     0.61 
 1987     0.04 
 1988     0.75 
 1989    -0.29 
 1990    -0.48 
 1991     1.37 
 1992     -1.3 
 1993     0.17 
 1994     0.53 
 1995     2.52 
 1996     -0.2 
 1997     0.93 
 1998     0.06 
 1999     0.68 
 2000      0.6 
 2001     0.68 
 2002     2.26 
 2003     1.74 
 2004     0.75 
 2005     2.05 
 2006     1.83 
 2007     2.23 
 2008     1.52 
 2009     1.18 
 2010     1.85 
 2011     0.79 
 2012     0.88 
 2013     1.24 
 2014     1.64 
 2015     1.67 
 2016     2.06 
 2017     1.55 
 2018     2.88