(1) All tariff publications and supplements thereto must indicate changes to existing rates or charges, rules, regulations or practices, or classifications by use of the appropriate symbols provided in the tariff's approved symbols page pursuant to ARM 38.3.2607(1) (g) .

(2) Explanation of such symbols must be provided in the approved symbols page and in the tariff or supplement in which used, and these symbols shall not be used for any other purpose.