# year    value 
 1900    -0.52 
 1901     0.12 
 1902     0.49 
 1903    -0.14 
 1904    -0.68 
 1905     -0.3 
 1906    -0.83 
 1907    -0.23 
 1908    -0.17 
 1909    -0.93 
 1910    -0.77 
 1911    -0.89 
 1912      0.2 
 1913    -1.34 
 1914     0.91 
 1915    -0.91 
 1916     0.22 
 1917    -1.03 
 1918     0.19 
 1919     -1.1 
 1920    -0.17 
 1921     0.07 
 1922    -1.25 
 1923     -0.6 
 1924    -0.17 
 1925    -0.37 
 1926     1.41 
 1927     -0.5 
 1928    -0.65 
 1929    -2.14 
 1930    -1.22 
 1931    -1.03 
 1932     -0.2 
 1933    -1.62 
 1934     0.65 
 1935      0.8 
 1936    -1.11 
 1937    -0.85 
 1938    -0.18 
 1939     0.01 
 1940      0.9 
 1941     0.93 
 1942    -0.66 
 1943     0.21 
 1944     0.45 
 1945    -1.72 
 1946     0.49 
 1947    -0.95 
 1948     0.24 
 1949    -0.22 
 1950     -1.2 
 1951    -0.65 
 1952     0.19 
 1953      0.1 
 1954    -0.17 
 1955    -0.57 
 1956    -0.19 
 1957    -1.36 
 1958     1.09 
 1959     0.64 
 1960     0.44 
 1961     0.36 
 1962     0.33 
 1963     1.21 
 1964    -0.58 
 1965    -0.01 
 1966     0.45 
 1967    -0.39 
 1968    -0.51 
 1969    -1.81 
 1970     0.62 
 1971    -0.03 
 1972    -0.59 
 1973     0.12 
 1974    -0.13 
 1975    -0.27 
 1976     0.48 
 1977    -0.53 
 1978     0.22 
 1979     0.45 
 1980     0.66 
 1981     1.13 
 1982     0.74 
 1983     0.81 
 1984     0.06 
 1985     -0.8 
 1986     0.69 
 1987     1.18 
 1988     0.84 
 1989     0.89 
 1990     1.27 
 1991     0.99 
 1992     1.16 
 1993      0.6 
 1994     1.12 
 1995     1.71 
 1996     0.83 
 1997     1.53 
 1998     1.49 
 1999     2.23 
 2000     1.14 
 2001     0.54 
 2002     1.85 
 2003      1.1 
 2004     1.64 
 2005     0.26 
 2006     0.74 
 2007     2.01 
 2008     0.18 
 2009     1.23 
 2010     0.78 
 2011     0.64 
 2012    -0.07 
 2013     0.39 
 2014     1.22 
 2015     2.44 
 2016     1.87 
 2017     1.73 
 2018     1.51