All corporations, companies and associations not incorporated under the laws of this state, and which are engaged in the city in effecting fire insurance, shall pay to the City Treasurer annually on or before July 15 of each year, a sum equal to 2% of the gross receipts of premiums by such corporation, company or association, or their agency or agents, for business effected or transacted for fire insurance within the city for the year ending July 1 preceding.
('68 Code, § 35.01)