# year value 1880 -0.7 1881 -0.41 1882 0.23 1883 -0.65 1884 -0.14 1885 0.9 1886 -0.74 1887 -0.95 1888 0.12 1889 0.29 1890 -0.64 1891 -0.86 1892 -0.51 1893 -0.31 1894 -0.63 1895 -0.34 1896 -0.3 1897 -0.06 1898 -0.3 1899 -0.45 1900 -0.08 1901 -0.14 1902 -0.46 1903 -0.94 1904 -0.84 1905 -0.55 1906 -0.74 1907 -0.58 1908 -0.78 1909 -0.37 1910 -0.48 1911 -0.39 1912 -0.1 1913 -0.36 1914 -0.22 1915 0.17 1916 -0.36 1917 -0.57 1918 -0.18 1919 -0.3 1920 -0.22 1921 -0.37 1922 -0.17 1923 -0.29 1924 -0.3 1925 -0.52 1926 0.17 1927 -0.04 1928 0.31 1929 -0.02 1930 -0.31 1931 -0.48 1932 -0.1 1933 -0.34 1934 -0.49 1935 -0.13 1936 -0.01 1937 0 1938 -0.06 1939 -0.57 1940 -0.11 1941 -0.01 1942 -0.05 1943 -0.09 1944 0.2 1945 -0.07 1946 -0.03 1947 -0.26 1948 -0.12 1949 -0.19 1950 -0.42 1951 0.08 1952 -0.11 1953 -0.01 1954 -0.08 1955 -0.19 1956 -0.44 1957 0.1 1958 0 1959 0.1 1960 -0.01 1961 0.17 1962 0.1 1963 0.06 1964 -0.33 1965 -0.06 1966 -0.13 1967 0.03 1968 -0.07 1969 0.1 1970 0.07 1971 -0.08 1972 0.21 1973 0.11 1974 -0.27 1975 -0.11 1976 -0.12 1977 0.27 1978 -0.02 1979 0.32 1980 0.26 1981 0.11 1982 0.08 1983 0.44 1984 0.17 1985 0.16 1986 0.14 1987 0.6 1988 0.55 1989 0.21 1990 0.44 1991 0.4 1992 0.19 1993 0.3 1994 0.46 1995 0.72 1996 0.42 1997 0.9 1998 0.76 1999 0.33 2000 0.46 2001 0.39 2002 0.77 2003 0.68 2004 0.7 2005 0.76 2006 0.76 2007 0.74 2008 0.75 2009 0.96 2010 0.68 2011 0.64 2012 0.97 2013 0.86 2014 1.05 2015 1.27 2016 0.84 2017 0.97 2018 0.99