# year value 1880 -0.46 1881 -1.15 1882 -1.02 1883 0.29 1884 -0.04 1885 -1.08 1886 -0.72 1887 -0.59 1888 -0.6 1889 -0.69 1890 -1.15 1891 -1.68 1892 -0.45 1893 -0.95 1894 -1.33 1895 -0.77 1896 -1.48 1897 -0.29 1898 -0.71 1899 -1.08 1900 -0.43 1901 -0.63 1902 -0.27 1903 -0.42 1904 -0.82 1905 -0.5 1906 -0.32 1907 -0.59 1908 -0.84 1909 -0.28 1910 -0.11 1911 -0.8 1912 -0.33 1913 -0.37 1914 -0.17 1915 0.13 1916 -0.3 1917 -0.54 1918 -0.58 1919 -0.23 1920 -0.36 1921 -0.39 1922 -0.59 1923 -0.67 1924 -0.19 1925 -0.55 1926 -0.15 1927 -0.39 1928 -0.39 1929 -0.6 1930 -0.19 1931 -0.15 1932 -0.44 1933 -0.39 1934 0 1935 -0.5 1936 -0.06 1937 -0.28 1938 -0.15 1939 -0.32 1940 0.16 1941 0.04 1942 0.18 1943 -0.42 1944 0.19 1945 0.06 1946 -0.31 1947 0.06 1948 -0.02 1949 -0.21 1950 -0.09 1951 -0.11 1952 -0.06 1953 -0.2 1954 -0.22 1955 -0.14 1956 -0.35 1957 -0.04 1958 0.19 1959 0.18 1960 -0.15 1961 -0.03 1962 -0.06 1963 -0.04 1964 -0.24 1965 -0.09 1966 0.06 1967 -0.2 1968 -0.1 1969 0.24 1970 0.17 1971 -0.14 1972 0.14 1973 0.37 1974 -0.06 1975 0.08 1976 -0.19 1977 0.21 1978 0.14 1979 0.23 1980 0.26 1981 0.17 1982 0.23 1983 0.39 1984 0.13 1985 0.11 1986 0.28 1987 0.54 1988 0.53 1989 0.16 1990 0.32 1991 0.48 1992 0.37 1993 0.43 1994 0.21 1995 0.71 1996 0.49 1997 0.6 1998 1.04 1999 0.56 2000 0.27 2001 0.53 2002 0.64 2003 0.6 2004 0.38 2005 0.89 2006 0.73 2007 0.4 2008 0.59 2009 0.8 2010 0.77 2011 0.61 2012 0.55 2013 0.69 2014 0.79 2015 1.17 2016 1.06 2017 1.25 2018 0.63