Section 26. Immediately after July tenth, the county commissioners shall annually prepare a report on county affairs, showing their acts during the preceding fiscal year, so as to give the taxpayers of the county a full and clear understanding of its affairs and of the objects and methods of county expenditures. They shall state specifically what petitions relating to highways have been received, and what highways have been laid out, altered, relocated or discontinued, the manner of their alteration or new construction, the time of their intended completion, what have been completed, at what cost and at whose expense, and what remain to be completed, what damages or betterments have been awarded or estimated and to or against whom, what damages have been paid or betterments collected, and what suits are pending in relation thereto. They shall also state what highways have been laid out under orders stating that betterments are to be assessed, their action relative to public and private ways, what applications relative to state highways they have made to the department of highways, and, so far as ascertainable, what highways have been laid out within the county by said department, what have been constructed and at what expense, what sums expended by the commonwealth in the county for highways have been repaid by said county, what sums remain to be paid, and when. They shall also make a detailed statement of the repairs upon the several county buildings, stating separately the work done by contract and by day, and the money paid, and the liabilities incurred in the construction of new buildings, and shall also state what reservoirs, reservoir dams and mill dams have been examined by them under section forty-five of chapter two hundred and fifty-three. They shall present a table showing the salaries paid to county officers, stating separately those prescribed by law, a statement of the county debt, giving the date when each obligation will mature and the rate of interest, stating separately the loans made in anticipation of taxes and permanent loans, a statement of the amount of county taxes due and unpaid, and a list of the assets of the county, including land, buildings, furniture in jails and other public buildings.