# year    value 
 1900     0.96 
 1901    -0.65 
 1902    -1.09 
 1903     0.39 
 1904    -1.17 
 1905    -1.18 
 1906     0.32 
 1907     0.87 
 1908    -1.54 
 1909    -0.39 
 1910    -0.99 
 1911     0.86 
 1912     -3.1 
 1913     0.64 
 1914    -1.08 
 1915     -2.2 
 1916    -0.54 
 1917     0.17 
 1918    -0.55 
 1919    -1.06 
 1920    -1.39 
 1921    -0.27 
 1922    -2.21 
 1923     0.85 
 1924    -0.28 
 1925    -0.99 
 1926     1.67 
 1927     0.28 
 1928     0.45 
 1929     1.07 
 1930     0.87 
 1931    -1.45 
 1932     1.25 
 1933    -0.24 
 1934     0.27 
 1935     0.63 
 1936    -1.43 
 1937     0.01 
 1938     0.61 
 1939    -0.26 
 1940     0.16 
 1941    -1.55 
 1942     1.17 
 1943     0.86 
 1944    -0.27 
 1945     0.03 
 1946     0.06 
 1947     1.23 
 1948     0.39 
 1949     1.35 
 1950     0.03 
 1951      0.8 
 1952    -1.14 
 1953     0.61 
 1954     0.24 
 1955    -0.46 
 1956    -0.62 
 1957     0.04 
 1958     0.71 
 1959    -0.44 
 1960     0.33 
 1961     1.36 
 1962    -0.12 
 1963     1.18 
 1964      0.1 
 1965    -0.62 
 1966     0.55 
 1967     0.96 
 1968     0.24 
 1969     0.76 
 1970     0.56 
 1971    -0.76 
 1972    -1.37 
 1973    -0.18 
 1974    -1.34 
 1975     0.05 
 1976    -0.11 
 1977    -0.02 
 1978    -0.85 
 1979    -0.13 
 1980    -0.32 
 1981     0.15 
 1982     1.36 
 1983    -0.11 
 1984     0.38 
 1985    -0.17 
 1986     0.43 
 1987     1.49 
 1988     -0.4 
 1989    -0.21 
 1990     0.46 
 1991     0.33 
 1992     0.44 
 1993    -0.64 
 1994     1.11 
 1995    -0.03 
 1996    -0.42 
 1997     0.49 
 1998    -0.54 
 1999     0.81 
 2000     1.56 
 2001     0.15 
 2002     0.78 
 2003     0.25 
 2004     1.02 
 2005     0.65 
 2006     2.24 
 2007    -0.66 
 2008     0.46 
 2009     1.34 
 2010     0.07 
 2011     1.28 
 2012     1.42 
 2013     1.15 
 2014     2.16 
 2015     0.96 
 2016     1.02 
 2017     0.37 
 2018     2.04