(1) Unless the context otherwise requires, in this sub-chapter the meaning of the term "increase" shall include "decrease" and any other change or modification.

(2) No temporary rate increase shall be renewed or granted unless a carrier or bureau has demonstrated that the same should be done and is permitted by law.

(3) All rate increase tariff filings must be accompanied by a cover sheet setting forth the present rate, the proposed rate, and the percentage change for each affected item.