There is hereby levied an annual inspection fee and service charge upon every person, firm or corporation operating a telephone exchange or rendering telephone service in the city in an amount equal to 2% of the gross revenues for each current year, for exchange telephone transmission service rendered wholly within the corporate limits of the city to compensate the municipality for the expenses incurred and services rendered incident to the exercise of its police power, supervision, policy regulation and control during construction and operation of lines and equipment of said telephone company in said municipality. Said fee shall be due and payable on or before March 1 of each year and shall be paid into, and expended from, the General Fund of the city.