# year    value 
 1980    -0.32 
 1981     0.11 
 1982     1.33 
 1983    -0.09 
 1984     0.42 
 1985    -0.14 
 1986     0.46 
 1987     1.51 
 1988     -0.4 
 1989    -0.21 
 1990     0.47 
 1991     0.36 
 1992     0.44 
 1993    -0.64 
 1994     1.12 
 1995    -0.04 
 1996    -0.43 
 1997     0.49 
 1998    -0.55 
 1999     0.78 
 2000     1.55 
 2001     0.13 
 2002     0.79 
 2003     0.23 
 2004     1.02 
 2005     0.64 
 2006     2.26 
 2007    -0.68 
 2008     0.47 
 2009     1.35 
 2010     0.09 
 2011     1.29 
 2012     1.49 
 2013     1.16 
 2014     2.19 
 2015     0.96 
 2016        1 
 2017     0.35 
 2018     2.08