The business tax for operating any vehicle as a taxicab for hire within the city more than three times in any one year is levied for such operation in the sum of twenty dollars per year for each vehicle so operated which shall be paid by the person in control of the operation, unless the vehicle is a replacement for such a vehicle discontinued for such use within the year and for which the business tax has been paid. (Ord. 2063 § 2 (part), 1975).