Every motor carrier subject to the road tax imposed by this article shall make to the commissioner on or before the last day of April, July, October, and January such reports of its operations during the quarter of the year ending on the last day of the preceding month as the commissioner requires. The commissioner may by regulation permit motor carriers having an annual road tax not in excess of an amount set by the commissioner to file annual reports. The commissioner by regulation may exempt from the reporting requirements of this Code section motor carriers all of whose operations are within this state.