1913    5.77      -9     165       .
    1914    5.92      -8     174       .
    1915    5.79      -7     188       .
    1916     4.8      -6     252       .
    1917    3.72      -5     342       .
    1918     4.5      -4     368       .
    1919    5.24      -3     429       .
    1920    5.21      -2     414       .
    1921    8.19      -1     471       .
    1922    7.04       0     488       .
    1923     6.4       1   576.2    0.08
    1924    6.52       2   627.5    1.32
    1925    6.21       3   696.3    2.87
    1926    6.41       4   767.9    5.19
    1927    6.76       5   822.5   10.39
    1928    6.23       6   884.2    8.73
    1929    6.37       7     980   14.33
    1930    7.41       8   971.8   16.90
    1931    9.04       9   914.6   22.57