Section 13
SEC. 13. In consideration of the franchise and rights hereby granted, the grantee shall pay to the Insular Government during the first ten years of the life of this franchise a tax of one per cent of the gross revenue received by the grantee from its operation under this franchise; and during the last fifteen years of the life of this franchise a tax of two per cent of such gross revenue. Such tax shall be due and payable quarterly and shall be in lieu of all taxes of any kind, nature or description, established or collected by any municipal, provincial or Insular authority. The grantee shall pay the tax on its real property in conformity with existing law.