1901  50.42   1.20
  1904  50.32   2.46
  1906  50.70   1.33
  1908  50.55   1.60
  1911  51.84   1.76
  1917  51.65   2.46
  1919  52.84   1.42
  1926  52.87   1.95
  1934  53.47   1.61
  1953  52.79   1.42
  1957  53.09   2.37
  1960  53.76   2.49
  1963  52.87   2.21
  1967  52.62   2.60
  1970  52.43   1.69
  1980  52.68   1.99
  1987  52.49   1.19
  1988  52.36   2.32