Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.6/hamster/overview_totals.py", line 233, in on_statistics_button_clicked
    dialogs.stats.show(self)
  File "/usr/lib/pymodules/python2.6/hamster/configuration.py", line 98, in show
    dialog = self.get_dialog_class()(parent, **kwargs)
  File "/usr/lib/pymodules/python2.6/hamster/stats.py", line 68, in __init__
    self.stats()
  File "/usr/lib/pymodules/python2.6/hamster/stats.py", line 235, in stats
    means = (sum([fact[0] for fact in by_weekday[day]]) / n,
ZeroDivisionError: integer division or modulo by zero