# year    value 
 1900     -0.5 
 1901    -0.77 
 1902     0.84 
 1903    -0.76 
 1904     -0.5 
 1905    -0.62 
 1906     1.04 
 1907    -1.21 
 1908    -0.51 
 1909    -0.37 
 1910    -1.65 
 1911    -0.82 
 1912    -0.55 
 1913     0.21 
 1914    -0.82 
 1915    -0.56 
 1916    -0.06 
 1917    -1.52 
 1918    -0.67 
 1919     0.62 
 1920     0.65 
 1921    -0.15 
 1922    -1.08 
 1923    -0.81 
 1924    -1.41 
 1925    -0.39 
 1926     -0.2 
 1927    -0.17 
 1928     -0.8 
 1929    -0.15 
 1930     0.08 
 1931    -0.96 
 1932    -0.36 
 1933    -0.06 
 1934    -0.69 
 1935     0.89 
 1936     0.17 
 1937    -0.33 
 1938     -0.7 
 1939    -0.51 
 1940     0.31 
 1941    -0.66 
 1942    -0.63 
 1943    -0.14 
 1944    -0.11 
 1945      0.8 
 1946     0.08 
 1947    -0.14 
 1948    -0.35 
 1949     0.15 
 1950     0.12 
 1951    -0.29 
 1952     0.39 
 1953     0.16 
 1954    -0.28 
 1955     -0.7 
 1956    -1.01 
 1957      0.5 
 1958    -0.13 
 1959    -0.42 
 1960    -0.32 
 1961     0.24 
 1962    -0.11 
 1963     0.05 
 1964    -0.18 
 1965    -0.23 
 1966     0.15 
 1967     0.58 
 1968    -0.66 
 1969     0.73 
 1970     0.49 
 1971    -0.67 
 1972     0.26 
 1973     0.32 
 1974    -0.04 
 1975     0.09 
 1976    -0.58 
 1977     0.18 
 1978     0.27 
 1979        0 
 1980     0.83 
 1981     0.87 
 1982     0.48 
 1983      1.1 
 1984      0.3 
 1985     0.55 
 1986     0.52 
 1987     0.45 
 1988     0.26 
 1989     0.02 
 1990     0.22 
 1991        1 
 1992     1.02 
 1993     0.59 
 1994     0.83 
 1995     0.54 
 1996     0.61 
 1997        1 
 1998     0.99 
 1999     0.05 
 2000     0.22 
 2001     0.38 
 2002     0.87 
 2003     0.67 
 2004     0.34 
 2005     0.47 
 2006     0.39 
 2007     0.21 
 2008      0.2 
 2009     1.19 
 2010     0.78 
 2011     0.42 
 2012     0.82 
 2013     0.66 
 2014     0.56 
 2015     1.38 
 2016     0.66 
 2017     0.93 
 2018     1.12