# year    value 
 1900     0.81 
 1901     0.46 
 1902     0.61 
 1903    -1.48 
 1904    -0.01 
 1905     0.17 
 1906    -0.21 
 1907     1.24 
 1908     0.63 
 1909        0 
 1910    -2.63 
 1911     0.11 
 1912    -0.62 
 1913     -2.1 
 1914    -0.06 
 1915    -1.24 
 1916    -0.79 
 1917    -2.64 
 1918     0.82 
 1919    -0.99 
 1920    -0.26 
 1921     0.47 
 1922     -1.7 
 1923    -0.29 
 1924    -0.25 
 1925    -0.61 
 1926        1 
 1927     0.36 
 1928    -0.67 
 1929    -2.76 
 1930     0.03 
 1931    -0.17 
 1932    -2.07 
 1933    -3.27 
 1934     2.82 
 1935     0.78 
 1936    -0.74 
 1937    -3.14 
 1938        1 
 1939     -0.7 
 1940     1.48 
 1941     1.45 
 1942     -0.7 
 1943     0.74 
 1944    -0.64 
 1945     0.48 
 1946    -0.48 
 1947     0.58 
 1948     -0.4 
 1949    -4.16 
 1950    -0.89 
 1951     0.93 
 1952     -1.5 
 1953     1.51 
 1954     1.32 
 1955    -1.73 
 1956    -0.11 
 1957    -0.18 
 1958     1.81 
 1959     1.21 
 1960       -1 
 1961     0.82 
 1962    -1.08 
 1963     0.81 
 1964    -1.19 
 1965     0.47 
 1966    -0.78 
 1967     0.89 
 1968    -0.23 
 1969    -0.89 
 1970     1.49 
 1971     0.15 
 1972    -0.62 
 1973    -1.69 
 1974    -0.03 
 1975    -0.78 
 1976     0.84 
 1977     0.17 
 1978     1.19 
 1979    -2.97 
 1980     1.19 
 1981     2.52 
 1982     0.13 
 1983     1.13 
 1984    -0.86 
 1985    -1.87 
 1986     1.08 
 1987     0.31 
 1988    -0.24 
 1989    -1.56 
 1990     0.35 
 1991    -0.47 
 1992     1.15 
 1993    -1.72 
 1994     0.76 
 1995     2.02 
 1996     1.44 
 1997     0.63 
 1998     0.89 
 1999     1.45 
 2000        2 
 2001    -0.09 
 2002     0.13 
 2003     2.03 
 2004     0.26 
 2005     1.45 
 2006     1.16 
 2007     0.01 
 2008    -0.52 
 2009     0.65 
 2010    -0.26 
 2011     0.32 
 2012     0.87 
 2013    -0.37 
 2014     0.71 
 2015     3.04 
 2016     1.35 
 2017     0.11 
 2018     1.74