Fix week rounding computation.

apachedex/__init__.py

@@ -681,7 +681,7 @@ def _asMonthString(timestamp):
 def _asWeekString(timestamp):
   dt, _ = timestamp.split(' ')
   day, month, year = dt.split(':', 1)[0].split('/')
-  return '%s/%02i/%02i' % (year, MONTH_VALUE_DICT[month], int(day) / 7 * 7 + 1)
+  return '%s/%02i/%02i' % (year, MONTH_VALUE_DICT[month], (int(day) - 1) / 7 * 7 + 1)
 
 def _weekStringAsQuarterString(timestamp):
   year, month, _ = timestamp.split('/')