# year    value 
 1900 -18.13264 
 1901 -17.5128 
 1902 -17.82146 
 1903 -18.04764 
 1904 -18.12548 
 1905 -18.39506 
 1906 -18.04635 
 1907 -18.12837 
 1908 -17.94452 
 1909 -17.91326 
 1910 -18.02989 
 1911 -17.78743 
 1912 -17.98132 
 1913 -17.91339 
 1914 -18.32736 
 1915 -18.03271 
 1916 -17.6937 
 1917 -17.93919 
 1918 -17.61622 
 1919 -17.70194 
 1920 -17.41444 
 1921 -17.9086 
 1922 -17.74356 
 1923 -17.41355 
 1924 -17.51596 
 1925 -17.33117 
 1926 -17.36336 
 1927 -17.31198 
 1928 -17.65636 
 1929 -17.69001 
 1930 -17.60184 
 1931 -17.63331 
 1932 -17.63899 
 1933 -17.56972 
 1934 -17.73656 
 1935 -17.6571 
 1936 -17.59716 
 1937 -17.60968 
 1938 -17.66041 
 1939 -17.27953 
 1940 -17.52988 
 1941 -17.51006 
 1942 -17.53167 
 1943 -17.41222 
 1944 -17.31441 
 1945 -17.48638 
 1946 -17.31462 
 1947 -17.59324 
 1948 -17.04562 
 1949 -17.23979 
 1950 -17.42018 
 1951 -17.38749 
 1952 -17.31978 
 1953 -17.34905 
 1954 -17.71986 
 1955 -17.57213 
 1956 -17.40216 
 1957 -17.38126 
 1958 -17.38934 
 1959 -17.30045 
 1960 -17.06843 
 1961 -17.40656 
 1962 -17.12177 
 1963 -17.17039 
 1964 -17.48851 
 1965 -17.77504 
 1966 -17.23982 
 1967 -17.52906 
 1968 -17.61935 
 1969 -17.35332 
 1970 -17.15998 
 1971 -17.50546 
 1972 -17.33024 
 1973 -17.06509 
 1974 -17.12315 
 1975 -17.09992 
 1976  -17.266 
 1977 -17.01831 
 1978 -16.99923 
 1979 -16.88067 
 1980 -16.95845 
 1981 -16.88782 
 1982 -16.94036 
 1983 -16.97517 
 1984 -16.92175 
 1985 -16.9722 
 1986 -16.73631 
 1987 -16.75271 
 1988  -16.547 
 1989 -16.54944 
 1990 -16.44975 
 1991 -16.38508 
 1992 -16.51317 
 1993 -16.37862 
 1994 -16.74597 
 1995 -16.89783 
 1996 -16.49027 
 1997 -16.1819 
 1998 -16.15857 
 1999 -16.28844 
 2000 -16.13011 
 2001 -15.67135 
 2002 -15.88904 
 2003 -15.4751 
 2004 -15.54202 
 2005 -15.27803