On or before the first Monday in June of each year, or on such date in each year as shall be fixed by the mayor and council, the manager shall submit to the mayor and council the estimates of each department and his own personal report and recommendation and estimate as to the probable expenditures of the city for the next ensuing fiscal year, stating the amount in detail required to meet all expenditures necessary for city purposes, including interest and sinking funds, and outstanding indebtedness, if any there be; also an estimate of the amount of income expected from all sources in each department, and the probable amount required to be raised by taxation to cover such expenditures, interest and sinking fund.