All services shall be billed on a monthly basis. The billing period for water service shall extend from the sixteenth day of one calendar month to the fifteenth day of the succeeding calendar month. The billing period for garbage collection and sewer service shall extend from the first to the last day of each calendar month. Any lot, property, building or residence owned or occupied for a period of at least one month shall be entitled to a refund for any full billing period during which the premises were unowned or unoccupied. (Ord. 551 §1, 2002)