# year value 1880 -0.35 1881 -0.27 1882 -0.28 1883 -0.05 1884 -0.41 1885 -0.75 1886 -0.36 1887 -0.6 1888 -0.64 1889 0.03 1890 -0.01 1891 -0.14 1892 -0.36 1893 -0.41 1894 -0.41 1895 -0.49 1896 -0.18 1897 -0.39 1898 -0.83 1899 0 1900 -0.79 1901 -0.24 1902 0.1 1903 -0.52 1904 -0.08 1905 -0.24 1906 -0.17 1907 -0.58 1908 -0.45 1909 -0.52 1910 -0.36 1911 -0.52 1912 -0.27 1913 -0.4 1914 0.08 1915 -0.46 1916 -0.2 1917 -0.76 1918 -0.28 1919 0.26 1920 -0.19 1921 0.19 1922 -0.12 1923 0.18 1924 -0.86 1925 -0.21 1926 -0.38 1927 -0.37 1928 -0.06 1929 -0.38 1930 0.14 1931 -0.65 1932 -0.09 1933 -0.06 1934 -0.03 1935 0.06 1936 -0.27 1937 -0.23 1938 0.27 1939 -0.13 1940 -0.12 1941 -0.62 1942 -0.32 1943 -0.11 1944 -0.2 1945 0.16 1946 -0.37 1947 -0.03 1948 -0.51 1949 -0.39 1950 0.11 1951 -0.15 1952 -0.17 1953 0.2 1954 -0.16 1955 -0.3 1956 -0.51 1957 0.28 1958 0.06 1959 -0.45 1960 -0.25 1961 -0.08 1962 0.13 1963 -0.16 1964 -0.37 1965 -0.4 1966 0.11 1967 0.27 1968 -0.01 1969 -0.04 1970 0.06 1971 -0.12 1972 0.08 1973 0.2 1974 0.39 1975 0.22 1976 -0.27 1977 -0.01 1978 0.47 1979 0.15 1980 0.7 1981 0.57 1982 0.51 1983 0.18 1984 -0.2 1985 0.27 1986 0.28 1987 0.17 1988 0.27 1989 0.52 1990 0.36 1991 0.64 1992 0.14 1993 0.33 1994 0.48 1995 0.03 1996 0.39 1997 0.41 1998 0.65 1999 0.45 2000 0.29 2001 0.18 2002 0.28 2003 0.53 2004 0.31 2005 0.53 2006 0.12 2007 0.53 2008 0.45 2009 0.71 2010 0.75 2011 0.5 2012 0.48 2013 0.82 2014 0.55 2015 0.81 2016 0.76 2017 0.84 2018 1.19 2019 0.88