Every sleeping car company, parlor or palace car company, dining car company, chair car company, or equipment company operating cars of any kind for carrying passengers or serving meals over any railroad in this state shall also, in addition to the said foregoing requirements, show by each of its statements:
(1) The total mileage traveled by the cars of said company during the next preceding 12 months, whether within this state or beyond its borders, and
(2) The total mileage traveled by such cars within the state during the same period.