# year value 1880 -0.81 1881 -0.23 1882 -0.31 1883 -1.19 1884 -1.28 1885 -0.83 1886 -0.61 1887 -0.4 1888 -0.86 1889 0.07 1890 -0.41 1891 -0.38 1892 -1.03 1893 -0.51 1894 0.02 1895 -0.14 1896 -0.72 1897 -0.24 1898 -1.08 1899 -0.39 1900 -0.27 1901 0.5 1902 -0.32 1903 -0.18 1904 -0.8 1905 -0.57 1906 0.22 1907 -1.05 1908 -0.86 1909 -0.94 1910 0.45 1911 -0.35 1912 -0.64 1913 -0.29 1914 0.17 1915 -0.21 1916 -0.61 1917 -1.04 1918 -0.35 1919 -0.6 1920 0.35 1921 0.53 1922 0.27 1923 -0.8 1924 -0.56 1925 0.19 1926 -0.42 1927 -0.14 1928 -0.79 1929 -0.46 1930 0.37 1931 -0.29 1932 -0.34 1933 -0.39 1934 0 1935 -0.29 1936 -0.34 1937 -0.14 1938 0.6 1939 -0.11 1940 0.02 1941 -0.1 1942 -0.07 1943 0 1944 0.33 1945 0.1 1946 0.34 1947 0.04 1948 0.12 1949 -0.18 1950 -0.05 1951 0.22 1952 -0.12 1953 0.31 1954 -0.82 1955 -0.26 1956 -0.83 1957 -0.18 1958 -0.07 1959 0.35 1960 -0.77 1961 0.68 1962 0.42 1963 0.04 1964 -0.39 1965 -0.31 1966 0.2 1967 0.21 1968 0.77 1969 -0.62 1970 -0.2 1971 -0.35 1972 -0.09 1973 0.51 1974 -0.03 1975 0.38 1976 -0.29 1977 1.23 1978 0.15 1979 0.03 1980 -0.2 1981 0.84 1982 0.12 1983 0.5 1984 0.07 1985 0.19 1986 0.66 1987 0.12 1988 0.55 1989 0.77 1990 1.34 1991 0.71 1992 0.29 1993 0.4 1994 0.68 1995 0.82 1996 -0.27 1997 0.75 1998 1.12 1999 0.95 2000 1.61 2001 1.61 2002 0.91 2003 0.61 2004 1.08 2005 1.17 2006 1.43 2007 1.42 2008 1.57 2009 0.91 2010 1.26 2011 0.95 2012 1.98 2013 0.85 2014 1.33 2015 1.45 2016 2.03 2017 1.63 2018 1.41 2019 1.55