# year    value 
 1900     0.95 
 1901     0.36 
 1902     0.64 
 1903    -0.46 
 1904    -0.15 
 1905     0.49 
 1906    -0.53 
 1907    -0.92 
 1908     0.29 
 1909       -1 
 1910     2.27 
 1911     0.86 
 1912    -1.19 
 1913    -0.55 
 1914     0.39 
 1915    -0.39 
 1916     0.17 
 1917    -1.71 
 1918     0.71 
 1919    -0.27 
 1920    -1.12 
 1921     0.52 
 1922    -0.07 
 1923    -0.72 
 1924    -1.23 
 1925     1.59 
 1926     0.52 
 1927     0.28 
 1928     0.61 
 1929      0.1 
 1930     0.56 
 1931    -0.02 
 1932    -0.13 
 1933     0.07 
 1934     2.19 
 1935    -0.47 
 1936     1.05 
 1937      0.1 
 1938     0.85 
 1939     1.14 
 1940     0.51 
 1941     0.68 
 1942     0.32 
 1943    -0.12 
 1944     -0.6 
 1945    -0.07 
 1946      1.6 
 1947    -0.49 
 1948    -0.22 
 1949     0.58 
 1950     -1.1 
 1951       -1 
 1952    -0.38 
 1953    -0.35 
 1954    -0.38 
 1955      0.3 
 1956     0.01 
 1957    -0.28 
 1958    -0.12 
 1959     0.51 
 1960    -0.58 
 1961      0.1 
 1962    -0.05 
 1963     1.19 
 1964    -0.11 
 1965       -1 
 1966     0.41 
 1967     0.03 
 1968     0.27 
 1969    -0.29 
 1970    -0.76 
 1971    -0.23 
 1972     0.99 
 1973     0.18 
 1974     0.77 
 1975    -1.27 
 1976     0.25 
 1977      1.5 
 1978     0.57 
 1979    -0.44 
 1980     0.18 
 1981     1.43 
 1982     -0.2 
 1983     -0.7 
 1984     0.09 
 1985     1.71 
 1986     1.77 
 1987     1.56 
 1988     1.07 
 1989     0.94 
 1990     0.73 
 1991     1.11 
 1992     1.68 
 1993     0.53 
 1994     1.42 
 1995    -0.43 
 1996    -0.16 
 1997     0.02 
 1998     0.42 
 1999     0.53 
 2000     1.92 
 2001     1.03 
 2002    -0.59 
 2003     0.87 
 2004     1.94 
 2005     0.96 
 2006      1.8 
 2007     1.61 
 2008     0.13 
 2009     0.36 
 2010     0.85 
 2011     0.23 
 2012     3.04 
 2013    -0.27 
 2014     0.54 
 2015     1.48 
 2016      1.9 
 2017     1.62 
 2018     1.02