1905   -0.45
  1906   -0.14
  1907   -0.28
  1908   -0.47
  1909   -0.98
  1910   -1.34
  1911   -1.04
  1912   -1.21
  1913   -1.01
  1914    0.03
  1915   -1.11
  1916   -0.81
  1917   -1.18
  1918   -0.80
  1919   -0.39
  1920   -0.35
  1921   -0.57
  1922   -0.50
  1923   -0.71
  1924   -0.63
  1925   -0.44
  1926   -0.35
  1927   -0.45
  1928   -0.31
  1929   -0.39
  1930   -0.37
  1931   -0.49
  1932   -0.11
  1933   -0.08
  1934   -0.15
  1935    0.28
  1936   -0.65
  1937    0.03
  1938    0.40
  1939    0.53
  1940    0.07
  1941    0.50
  1942    0.50
  1943    0.37
  1944   -0.22
  1945    0.56
  1946    1.14
  1947    0.25
  1948    0.57
  1949    0.27
  1950   -0.33
  1951   -0.22
  1952   -0.43
  1953   -0.06
  1954   -0.72
  1955   -0.33
  1956   -0.85
  1957   -0.75
  1958   -0.21
  1959   -0.19
  1960   -0.36
  1961   -0.13
  1962   -0.44
  1963   -0.11
  1964   -0.40
  1965   -0.39
  1966   -0.28
  1967   -0.78
  1968   -0.50
  1969   -0.81
  1970   -0.61
  1971   -0.38
  1972   -0.45
  1973    0.01
  1974   -0.57
  1975   -0.07
  1976   -0.70
  1977   -0.29
  1978   -0.11
  1979   -0.09
  1980   -0.21
  1981   -0.22
  1982    0.04
  1983   -0.14
  1984   -0.65
  1985   -0.39
  1986   -0.28
  1987    0.08
  1988    0.09
  1989    0.12
  1990    0.52
  1991    0.19
  1992   -0.10
  1993   -0.03
  1994    0.55
  1995    0.29
  1996    0.01
  1997    0.43
  1998    1.16
  1999    0.86
  2000    0.35
  2001    0.72
  2002    0.92
  2003    0.68
  2004    0.88
  2005    0.60
  2006    1.11
  2007    1.35
  2008    0.80