# year value 1880 -0.59 1881 -0.36 1882 -0.32 1883 -0.78 1884 -1.15 1885 -0.83 1886 -0.66 1887 -0.56 1888 -0.92 1889 0.09 1890 -0.46 1891 -0.51 1892 -0.81 1893 -0.57 1894 -0.3 1895 -0.36 1896 -0.57 1897 -0.14 1898 -0.81 1899 -0.53 1900 -0.27 1901 0.11 1902 -0.46 1903 -0.24 1904 -0.55 1905 -0.36 1906 0.1 1907 -0.79 1908 -0.62 1909 -0.79 1910 -0.07 1911 -0.5 1912 -0.37 1913 -0.45 1914 -0.08 1915 -0.13 1916 -0.46 1917 -1.07 1918 -0.64 1919 -0.35 1920 0.08 1921 0.22 1922 0 1923 -0.54 1924 -0.33 1925 -0.1 1926 -0.2 1927 -0.32 1928 -0.4 1929 -0.49 1930 -0.03 1931 -0.22 1932 -0.13 1933 -0.26 1934 -0.15 1935 -0.26 1936 -0.16 1937 -0.15 1938 0.48 1939 -0.14 1940 0.05 1941 -0.1 1942 -0.02 1943 0.13 1944 0.06 1945 -0.01 1946 0.08 1947 0.11 1948 0 1949 -0.08 1950 -0.03 1951 0.02 1952 -0.03 1953 0.35 1954 -0.18 1955 -0.29 1956 -0.47 1957 -0.13 1958 0.14 1959 0.16 1960 -0.4 1961 0.21 1962 0.17 1963 -0.18 1964 -0.31 1965 -0.21 1966 -0.1 1967 0.14 1968 0.08 1969 -0.08 1970 0 1971 -0.27 1972 -0.15 1973 0.5 1974 -0.06 1975 0.26 1976 -0.21 1977 0.48 1978 0.14 1979 0.06 1980 0.33 1981 0.55 1982 0.09 1983 0.43 1984 0.22 1985 0.17 1986 0.44 1987 0.27 1988 0.65 1989 0.49 1990 0.98 1991 0.63 1992 0.33 1993 0.46 1994 0.54 1995 0.73 1996 0.31 1997 0.59 1998 1.09 1999 0.65 2000 0.97 2001 0.91 2002 0.94 2003 0.85 2004 0.8 2005 1.09 2006 0.88 2007 1.15 2008 0.96 2009 0.81 2010 1.38 2011 0.94 2012 1.16 2013 0.88 2014 1.2 2015 1.26 2016 1.81 2017 1.4 2018 1.18 2019 1.49