At the time of the issuance of the taxicab operator's license and annually thereafter, on or before January 1 of each calendar year, no taxicab operator operating in the City shall fail to pay to the Mayor or other duly authorized issuing authority the fees as provided hereinafter for each original and additional taxicab to be operated by it on the following basis:
(a) If put into operation between January 1 and June 30 of any year, for the balance of the calendar year, the sum of ten dollars ($10.00) per year; and
(b) If put into operation between July 1 and December 1 of any year, for the balance of the calendar year, the sum of seven dollars and fifty cents ($7.50).
Nothing in this section shall be construed to mean that there shall be a refund of any part or portion of any license fee so paid in case any taxicab is taken off the streets and not thereafter operated by such operator during the time for which a license has been issued.