# year    value 
 1900    -0.61 
 1901     -0.7 
 1902    -0.99 
 1903    -0.94 
 1904    -0.64 
 1905    -0.51 
 1906    -0.71 
 1907    -0.79 
 1908    -0.55 
 1909    -0.37 
 1910    -0.24 
 1911     0.03 
 1912        0 
 1913    -0.35 
 1914    -0.16 
 1915     0.03 
 1916    -0.96 
 1917    -0.05 
 1918    -0.74 
 1919    -0.34 
 1920    -0.38 
 1921    -0.81 
 1922    -0.79 
 1923     -1.2 
 1924     -0.8 
 1925    -0.72 
 1926    -0.42 
 1927     -0.7 
 1928    -0.44 
 1929    -0.48 
 1930    -0.66 
 1931    -0.47 
 1932    -0.17 
 1933    -0.29 
 1934     0.14 
 1935     0.06 
 1936     -0.2 
 1937    -0.11 
 1938    -0.32 
 1939     0.54 
 1940     0.66 
 1941      0.4 
 1942    -0.37 
 1943    -0.68 
 1944     0.12 
 1945     0.27 
 1946     0.04 
 1947     0.13 
 1948     -0.3 
 1949     0.14 
 1950      0.5 
 1951     0.31 
 1952    -0.15 
 1953    -0.27 
 1954    -0.33 
 1955    -0.84 
 1956    -0.01 
 1957    -0.22 
 1958     0.27 
 1959     0.15 
 1960    -0.09 
 1961     -0.1 
 1962     0.32 
 1963     0.02 
 1964    -0.51 
 1965     0.05 
 1966    -0.06 
 1967    -0.36 
 1968      0.4 
 1969     0.27 
 1970    -0.08 
 1971    -0.11 
 1972    -0.27 
 1973     0.09 
 1974     0.01 
 1975     0.22 
 1976     -0.3 
 1977     0.19 
 1978     0.27 
 1979     0.63 
 1980     0.42 
 1981      0.3 
 1982    -0.27 
 1983    -0.08 
 1984    -0.67 
 1985     0.77 
 1986     0.51 
 1987     0.66 
 1988     0.28 
 1989     0.33 
 1990     0.62 
 1991        0 
 1992    -0.16 
 1993     0.62 
 1994     0.35 
 1995    -0.33 
 1996     0.19 
 1997      0.6 
 1998     1.17 
 1999      0.6 
 2000     0.27 
 2001     0.31 
 2002     0.08 
 2003     0.74 
 2004     0.78 
 2005     0.59 
 2006      0.7 
 2007    -0.24 
 2008     0.53 
 2009     0.91 
 2010     0.27 
 2011     0.16 
 2012     0.34 
 2013     0.89 
 2014     1.02 
 2015     0.77 
 2016     0.97 
 2017     0.66 
 2018     0.28