Section 11-663. Additional tax on transportation corporations and associations

Every corporation, joint-stock  company  or  association  formed for or principally engaged in the conduct of aviation, steamboat,
  ferry  (except  a ferry company operating between any of the boroughs of
  the city under a lease granted by the city), or navigation  business  or
  formed  for or principally engaged in the conduct of two or more of such
  businesses, except a corporation,  joint-stock  company  or  association
  subject  to  taxation  under  subchapter  two  of chapter eleven of this
  title, shall pay for the privilege of carrying on its  business  in  the
  city,  a  tax  which shall be equal to five-tenths of one per centum for
  taxable years  ending  on  or  before  December  thirty-first,  nineteen
  hundred  seventy-four, and seventy-five hundredths of one per centum for
  taxable years beginning on or  after  January  first,  nineteen  hundred
  seventy-five  upon  its gross earnings from all sources within the city,
  excluding earnings derived from  business  of  a  character  other  than
  wholly intra-city. Provided, however, gross earnings from transportation
  business both originating and terminating within the city and traversing
  both  the  city  and  any other city, any state or states or any country
  shall be subject to the tax imposed by this section  and  such  earnings
  shall be allocated to the city in the same ratio that the mileage within
  the city bears to the total mileage of such business.