Improvements to real property completed during the period after July 1 in any year and through January 1 in the next succeeding year or otherwise first added to the tax rolls during this period are subject to the payment of property taxes for the six (6) months beginning on that January 1 and ending the next succeeding June 30. The taxes for these six (6) months shall be computed by using the assessed valuation of the property at one-half (1/2) the current tax rate. The taxes levied hereby shall be due and payable on January 1 or as of the day a tax bill therefor was or reasonably should have been received or available, whichever is later. The board of aldermen may establish by resolution a discount for payment prior to the time that interest shall be charged as hereafter provided. The taxes established hereby, if not paid sooner, shall bear interest from the first day of April or thirty (30) days after the bill for taxes has been mailed or made available, whichever is later, at the rate of two-thirds (2/3) per cent for each month or fraction of a month thereafter until paid. This tax, if not paid after the first day of the following July, shall be collected as provided in section 113 of this Charter. (Reso. 5-7-59, § 1; Reso. 9-5-63; Res. No. 3-77, § 1, 3-3-77)