Whenever the Council shall determine that the whole or any part of the expense of any public improvement shall be defrayed by special assessments upon the property especially benefited, it shall so declare by resolution. The resolution shall state the estimated cost of the improvement, what proportion of the its cost shall be paid by special assessments, and what part, if any, shall be paid from the general funds of the City. The resolution shall also state the number of installments in which assessments may be paid and shall designate the districts or land and premises upon which special assessments shall be levied.