# year value 1880 -0.23 1881 -0.34 1882 -0.41 1883 -0.24 1884 -0.69 1885 -0.56 1886 -0.36 1887 -0.36 1888 -0.51 1889 -0.3 1890 -0.21 1891 -0.47 1892 -0.21 1893 -0.18 1894 -0.26 1895 -0.29 1896 -0.18 1897 -0.01 1898 -0.11 1899 -0.29 1900 -0.11 1901 0.07 1902 -0.41 1903 -0.5 1904 -0.55 1905 -0.26 1906 0.01 1907 -0.48 1908 -0.45 1909 -0.22 1910 -0.2 1911 -0.17 1912 -0.51 1913 -0.41 1914 -0.11 1915 -0.03 1916 -0.24 1917 -0.29 1918 -0.41 1919 -0.16 1920 -0.12 1921 0.05 1922 -0.2 1923 -0.28 1924 -0.11 1925 -0.21 1926 -0.23 1927 -0.03 1928 -0.21 1929 -0.28 1930 0.08 1931 0.23 1932 -0.03 1933 -0.11 1934 -0.01 1935 -0.06 1936 0.2 1937 0.16 1938 0.13 1939 0.07 1940 0.1 1941 0.13 1942 0.03 1943 -0.06 1944 0.08 1945 0.03 1946 -0.12 1947 0.03 1948 0.06 1949 -0.12 1950 -0.23 1951 0.01 1952 0.1 1953 0.12 1954 -0.02 1955 0 1956 -0.3 1957 0.04 1958 0 1959 0.11 1960 0.06 1961 0.06 1962 0 1963 0.04 1964 -0.19 1965 -0.22 1966 0.12 1967 -0.12 1968 -0.18 1969 0.01 1970 0.05 1971 -0.14 1972 -0.03 1973 0.28 1974 -0.04 1975 0.1 1976 -0.19 1977 0.17 1978 -0.13 1979 0.14 1980 0.17 1981 0.32 1982 0.07 1983 0.39 1984 0.18 1985 0.08 1986 0.11 1987 0.41 1988 0.57 1989 0.35 1990 0.43 1991 0.54 1992 -0.04 1993 0.31 1994 0.38 1995 0.66 1996 0.39 1997 0.54 1998 1.07 1999 0.62 2000 0.52 2001 0.75 2002 0.77 2003 0.78 2004 0.53 2005 0.91 2006 0.9 2007 0.74 2008 0.68 2009 0.76 2010 1.07 2011 0.9 2012 0.99 2013 0.85 2014 0.91 2015 1.06 2016 1.27 2017 1.11 2018 0.96